Kayo Waki - Academia.edu (original) (raw)

Papers by Kayo Waki

Journal of Diabetes Investigation, 2017

Aims/Introduction: Preventing dropout is crucial in managing diabetes. Accordingly, we investigat... more Aims/Introduction: Preventing dropout is crucial in managing diabetes. Accordingly, we investigated whether patients who had dropped out of diabetic care are suitable candidates for the use of mobile technologiessuch as smartphone applicationsto support self-management (mHealth), which might help prevent dropout. Materials and Methods: We carried out a cross-sectional study in Tokyo, Japan. Patients aged 20 years or older who were clinically diagnosed as diabetic and who regularly visited the outpatient unit at the University of Tokyo Hospital were recruited between August 2014 and March 2015. Data were collected through face-to-face structured interviews, physical measurements and medical records. Participants were asked whether they were willing to use mHealth after being shown DialBeticsan mHealth application for diabeticsas an example, and about their history of dropout and previous mHealth experience. Data were analyzed by multivariate logistic regression models. Results: Of 307 patients with type 1 and type 2 diabetes, 34 (11.1%) had previously dropped out from diabetic care. Multivariate analysis identified previous mHealth experience as a negative predictor of dropout (odds ratio 0.211, P = 0.023). Of those 34 patients, 27 (79.4%) expressed willingness to use mHealth, a significantly higher percentage than for those who had never dropped out (51.5%, P = 0.002). After adjusting for confounders, history of dropout remained a strong predictor of willingness (odds ratio 3.870, P = 0.004). Conclusions: Patients who previously dropped out of diabetic care are suitable candidates for mHealth. Future studies must evaluate whether mHealth is effective for preventing repeated dropout and improving glycemic control among this population.

Journal of diabetes science and technology, Jan 16, 2015

Diabetes self-management education is an essential element of diabetes care. Systems based on inf... more Diabetes self-management education is an essential element of diabetes care. Systems based on information and communication technology (ICT) for supporting lifestyle modification and self-management of diabetes are promising tools for helping patients better cope with diabetes. An earlier study had determined that diet improved and HbA1c declined for the patients who had used DialBetics during a 3-month randomized clinical trial. The objective of the current study was to test a more patient-friendly version of DialBetics, whose development was based on the original participants' feedback about the previous version of DialBetics. DialBetics comprises 4 modules: data transmission, evaluation, exercise input, and food recording and dietary evaluation. Food recording uses a multimedia food record, FoodLog. A 1-week pilot study was designed to determine if usability and compliance improved over the previous version, especially with the new meal-input function. In the earlier 3-month,...

Bioscience trends, 2011

In the modern era of highly active antiretroviral therapy (HAART), reluctance to perform transpla... more In the modern era of highly active antiretroviral therapy (HAART), reluctance to perform transplantation (Tx) in HIV-infected individuals is no longer justified. Non-nucleoside reverse transcriptase inhibitors (NNRTIs) or protease inhibitors (PIs), the current first line regimens of HAART, are metabolized by the cytochrome P450 family (CYP3A4). Most NNRTIs induce CYP3A4, whereas PIs inhibit it. Calcinuerin inhibitors (CNIs), which are mandatory for Tx, need the same enzyme complex for their clearance. Therefore, a significant drug-drug interaction (DDI) is encountered between current HAART and CNIs. This results in extreme difficulty in adjusting the optimal dose of CNIs, for which the therapeutic range is narrow. Of interest, integrase inhibitors (INIs) - novel, potent anti-HIV drugs - are mainly metabolized by uridine diphosphate glucuronosyltransferase (UGT) 1A1 and do not induce or inhibit CYP3A4. DDI is presumably absent when NNTRIs or PIs are replaced by INIs. Raltegravir (RAL...

Clinical transplants, 2009

This chapter summarizes analyses of 51,060 adult primary liver-only transplants from deceased don... more This chapter summarizes analyses of 51,060 adult primary liver-only transplants from deceased donors reported to the OPTN/UNOS Liver Transplant Registry from 1995 to 2009. Despite advances in surgical techniques and immunosuppression, analysis shows improvement in one-year graft but no improvement in long-term graft survival. Adoption of the Model for End-Stage Liver Disease (MELD) score for organ allocation--prioritizing sicker patients for transplantation--has significantly influenced liver transplant procedures. Accordingly, we classified the transplants into two groups: 1995-2001 (pre-MELD era) and 2002-2007 (MELD era), and our analyses found that long-term survival of liver grafts remained almost unchanged between the two eras. Patient pre-transplant status was better in the MELD era. But when we analyzed the grafts that survived more than one year, survival rates were slightly better pre-MELD than in the MELD era (82.2% and 80.34%, respectively) and risk of graft failure was s...

Pituitary, 1999

A 57-year-old woman presented with 2-year history of polyuria and polydipsia. Hormonal studies re... more A 57-year-old woman presented with 2-year history of polyuria and polydipsia. Hormonal studies revealed almost normal anterior pituitary function and central diabetes insipidus. Magnetic resonance imaging showed thickening of the pituitary stalk and enlargement of the neurohypophysis without high intensity of the posterior lobe on T1-weighted images, which were compatible with lymphocytic infundibuloneurohypophysitis. Transsphenoidal biopsy was done and histological examination disclosed moderate fibrosis and lymphocytic infiltration not only in the posterior pituitary, but also in the adjacent anterior pituitary part of the gland. The lymphocytes both in the anterior and posterior pituitary were mainly T cells that were positive for UCHL 1, CD 3, and CD 8. Immunofluorescence of frozen tissue detected immunecomplex deposition in small vessels and the interstitium. These findings suggested that allergic reactions may play an important role in the pathogenesis of lymphocytic infundibu...

Transplantation Journal, 2012

Transplantation, 2011

Coinfection by Hepatitis B virus (HBV) and hepatitis C virus (HCV) has been reported to increase ... more Coinfection by Hepatitis B virus (HBV) and hepatitis C virus (HCV) has been reported to increase risk of graft failure for liver transplant recipients. But other studies have controverted that finding. The aim of this study was to determine whether-after adjustments for other important predictors-HBV/HCV coinfection was associated with worse liver graft survival than HBV or HCV mono-infection. A retrospective cohort study examined Organ Procurement and Transplantation Network/United Network Organ Sharing data for 48,654 deceased-donor primary liver-only transplants that were performed on adults between January 1, 1995, and August 31, 2009, and that included recipient and donor HBV/HCV status. Recipients were classified into four groups: the HBV/HCV coinfected [B+/C+]; HBV mono-infected [B+/C-]; HCV mono-infected [B-/C+]; and hepatitis uninfected [B-/C-]. Kaplan-Meier methods were used to calculate liver graft survival rates, Cox proportional hazard models were used to estimate the effect of hepatitis virus infection, and adjusted for potential confounders. Graft survival rates were highest with B+/C-: 85.3% 1-year survival and 63.0% 10-year survival. Graft survival with B+/C+ was superior to survival with B-/C+: 83.5% 1-year survival and 53.6% 10-year survival vs. B-/C+: 82.9% 1-year survival and 46.1% 10-year survival. Survival with B-/C-: 83.6% 1-year survival and 56.6% 10-year survival was superior to survival with B+/C+ (shown above). After adjustment for confounders, and with the coinfected as reference, B-/C+ recipients had a higher risk of graft loss (hazard ratio, 1.35; 95% CI, 1.10-1.66); the other two groups had a lower risk. Our results suggested-despite reports to the contrary-statistically better graft outcomes with HBV/HCV coinfection than with HCV mono-infection.

Transplantation Journal, 2012

Transplant International, 2012

PLoS ONE, 2013

Objective: The effect of smoking cessation on the risk of diabetes has been reported previously. ... more Objective: The effect of smoking cessation on the risk of diabetes has been reported previously. However, it is unknown whether the association is influenced by weight gain and other potential risk factors.

Journal of Diabetes Science and Technology, 2014

Numerous diabetes-management systems and programs for improving glycemic control to meet guidelin... more Numerous diabetes-management systems and programs for improving glycemic control to meet guideline targets have been proposed, using IT technology. But all of them allow only limited-or no-real-time interaction between patients and the system in terms of system response to patient input; few studies have effectively assessed the systems' usability and feasibility to determine how well patients understand and can adopt the technology involved. DialBetics is composed of 4 modules: (1) data transmission module, (2) evaluation module, (3) communication module, and (4) dietary evaluation module. A 3-month randomized study was designed to assess the safety and usability of a remote health-data monitoring system, and especially its impact on modifying patient lifestyles to improve diabetes self-management and, thus, clinical outcomes. Fifty-four type 2 diabetes patients were randomly divided into 2 groups, 27 in the DialBetics group and 27 in the non-DialBetics control group. HbA1c and fasting blood sugar (FBS) values declined significantly in the DialBetics group: HbA1c decreased an average of 0.4% (from 7.1 ± 1.0% to 6.7 ± 0.7%) compared with an average increase of 0.1% in the non-DialBetics group (from 7.0 ± 0.9% to 7.1 ± 1.1%) (P = .015); The DialBetics group FBS decreased an average of 5.5 mg/dl compared with a non-DialBetics group average increase of 16.9 mg/dl (P = .019). BMI improvement-although not statistically significant because of the small sample size-was greater in the DialBetics group. DialBetics was shown to be a feasible and an effective tool for improving HbA1c by providing patients with real-time support based on their measurements and inputs.

Journal of Diabetes Science and Technology, 2012

Healthcare providers lack the time to provide the continuous life-style education necessary for d... more Healthcare providers lack the time to provide the continuous life-style education necessary for diabetes patients to gain enough skill in diabetes selfmanagement. We developed a real-time, partially automated interactive smartphone-based system (DialBetics)-combining IT and "natural language processing"-to interpret patients' blood glucose, blood pressure, weight, exercise, and dietary content calculated from a message and photo of a meal sent by patients, and respond with communication of findings and advice, achieving diabetes selfmanagement. We examined safety, usability, and impact of a remote health-data monitoring and education system on self-management. Five patients with type 2 diabetes were recruited for a one-month feasibility study. The patients were provided with smartphone, glucometer, blood pressure monitor, pedometer, and weight scale. Patients' measurements were automatically transmitted to a server; exercise and diet information with a meal photo were sent by patients. Patients had excellent compliance for measurements; patients' interest in, and willingness to make, life-style changes improved by receiving real-time findings and advice from DialBetics. Considering the four-week time period of this intervention, results are encouraging in improving self-management. We also plan to assess the impact of DialBetics on patient HbA1c outcomes.

In patients with end-stage chronic kidney disease (CKD) and type 1 diabetes mellitus (DM 1), simu... more In patients with end-stage chronic kidney disease (CKD) and type 1 diabetes mellitus (DM 1), simultaneous pancreas-kidney (SPK) transplantation is currently considered the gold standard therapy. The aim of this study was to analyze and report the long-term clinical outcomes of the 23 SPK transplantations performed at our institution over an 84-month period (January 1, 2000 to December 31, 2006. A prospective analysis of these patients included donor, recipient, and transplantation characteristics. The only requirements for transplantation were blood group compatibility and a negative cross-match. Bladder drainage via pancreaticoduodenocystostomy was performed in all of the patients. Due to a pulmonary embolus 1 patient (4.3%) died at 2 months. The actuarial patient survival rates at 3 months and 1, 3, and 5 years were 95.6%. Causes for the renal graft loss were chronic allograft nephropathy in 3 cases (13%) and death of the patient in 1 case (4.3%). The actuarial censored renal allograft survival rates at 3 months and at 1 year were 100%, and at 3 and 5 years were 91.3%. Causes for the renal graft loss were chronic rejection in 1 case (4.3%) and patient death in 1 case (4.3%). The actuarial censored pancreatic allograft survival rates at 3 months and at 1 and 3 years were 100%, and at 5 years was 95.6%. The results of this work add further evidence that SPK is the gold standard therapy for selected patients with end-stage CKD due to DM 1.

Journal of Diabetes Investigation, 2017

Aims/Introduction: Preventing dropout is crucial in managing diabetes. Accordingly, we investigat... more Aims/Introduction: Preventing dropout is crucial in managing diabetes. Accordingly, we investigated whether patients who had dropped out of diabetic care are suitable candidates for the use of mobile technologiessuch as smartphone applicationsto support self-management (mHealth), which might help prevent dropout. Materials and Methods: We carried out a cross-sectional study in Tokyo, Japan. Patients aged 20 years or older who were clinically diagnosed as diabetic and who regularly visited the outpatient unit at the University of Tokyo Hospital were recruited between August 2014 and March 2015. Data were collected through face-to-face structured interviews, physical measurements and medical records. Participants were asked whether they were willing to use mHealth after being shown DialBeticsan mHealth application for diabeticsas an example, and about their history of dropout and previous mHealth experience. Data were analyzed by multivariate logistic regression models. Results: Of 307 patients with type 1 and type 2 diabetes, 34 (11.1%) had previously dropped out from diabetic care. Multivariate analysis identified previous mHealth experience as a negative predictor of dropout (odds ratio 0.211, P = 0.023). Of those 34 patients, 27 (79.4%) expressed willingness to use mHealth, a significantly higher percentage than for those who had never dropped out (51.5%, P = 0.002). After adjusting for confounders, history of dropout remained a strong predictor of willingness (odds ratio 3.870, P = 0.004). Conclusions: Patients who previously dropped out of diabetic care are suitable candidates for mHealth. Future studies must evaluate whether mHealth is effective for preventing repeated dropout and improving glycemic control among this population.

Journal of diabetes science and technology, Jan 16, 2015

Diabetes self-management education is an essential element of diabetes care. Systems based on inf... more Diabetes self-management education is an essential element of diabetes care. Systems based on information and communication technology (ICT) for supporting lifestyle modification and self-management of diabetes are promising tools for helping patients better cope with diabetes. An earlier study had determined that diet improved and HbA1c declined for the patients who had used DialBetics during a 3-month randomized clinical trial. The objective of the current study was to test a more patient-friendly version of DialBetics, whose development was based on the original participants' feedback about the previous version of DialBetics. DialBetics comprises 4 modules: data transmission, evaluation, exercise input, and food recording and dietary evaluation. Food recording uses a multimedia food record, FoodLog. A 1-week pilot study was designed to determine if usability and compliance improved over the previous version, especially with the new meal-input function. In the earlier 3-month,...

Bioscience trends, 2011

In the modern era of highly active antiretroviral therapy (HAART), reluctance to perform transpla... more In the modern era of highly active antiretroviral therapy (HAART), reluctance to perform transplantation (Tx) in HIV-infected individuals is no longer justified. Non-nucleoside reverse transcriptase inhibitors (NNRTIs) or protease inhibitors (PIs), the current first line regimens of HAART, are metabolized by the cytochrome P450 family (CYP3A4). Most NNRTIs induce CYP3A4, whereas PIs inhibit it. Calcinuerin inhibitors (CNIs), which are mandatory for Tx, need the same enzyme complex for their clearance. Therefore, a significant drug-drug interaction (DDI) is encountered between current HAART and CNIs. This results in extreme difficulty in adjusting the optimal dose of CNIs, for which the therapeutic range is narrow. Of interest, integrase inhibitors (INIs) - novel, potent anti-HIV drugs - are mainly metabolized by uridine diphosphate glucuronosyltransferase (UGT) 1A1 and do not induce or inhibit CYP3A4. DDI is presumably absent when NNTRIs or PIs are replaced by INIs. Raltegravir (RAL...

Clinical transplants, 2009

This chapter summarizes analyses of 51,060 adult primary liver-only transplants from deceased don... more This chapter summarizes analyses of 51,060 adult primary liver-only transplants from deceased donors reported to the OPTN/UNOS Liver Transplant Registry from 1995 to 2009. Despite advances in surgical techniques and immunosuppression, analysis shows improvement in one-year graft but no improvement in long-term graft survival. Adoption of the Model for End-Stage Liver Disease (MELD) score for organ allocation--prioritizing sicker patients for transplantation--has significantly influenced liver transplant procedures. Accordingly, we classified the transplants into two groups: 1995-2001 (pre-MELD era) and 2002-2007 (MELD era), and our analyses found that long-term survival of liver grafts remained almost unchanged between the two eras. Patient pre-transplant status was better in the MELD era. But when we analyzed the grafts that survived more than one year, survival rates were slightly better pre-MELD than in the MELD era (82.2% and 80.34%, respectively) and risk of graft failure was s...

Pituitary, 1999

A 57-year-old woman presented with 2-year history of polyuria and polydipsia. Hormonal studies re... more A 57-year-old woman presented with 2-year history of polyuria and polydipsia. Hormonal studies revealed almost normal anterior pituitary function and central diabetes insipidus. Magnetic resonance imaging showed thickening of the pituitary stalk and enlargement of the neurohypophysis without high intensity of the posterior lobe on T1-weighted images, which were compatible with lymphocytic infundibuloneurohypophysitis. Transsphenoidal biopsy was done and histological examination disclosed moderate fibrosis and lymphocytic infiltration not only in the posterior pituitary, but also in the adjacent anterior pituitary part of the gland. The lymphocytes both in the anterior and posterior pituitary were mainly T cells that were positive for UCHL 1, CD 3, and CD 8. Immunofluorescence of frozen tissue detected immunecomplex deposition in small vessels and the interstitium. These findings suggested that allergic reactions may play an important role in the pathogenesis of lymphocytic infundibu...

Transplantation Journal, 2012

Transplantation, 2011

Coinfection by Hepatitis B virus (HBV) and hepatitis C virus (HCV) has been reported to increase ... more Coinfection by Hepatitis B virus (HBV) and hepatitis C virus (HCV) has been reported to increase risk of graft failure for liver transplant recipients. But other studies have controverted that finding. The aim of this study was to determine whether-after adjustments for other important predictors-HBV/HCV coinfection was associated with worse liver graft survival than HBV or HCV mono-infection. A retrospective cohort study examined Organ Procurement and Transplantation Network/United Network Organ Sharing data for 48,654 deceased-donor primary liver-only transplants that were performed on adults between January 1, 1995, and August 31, 2009, and that included recipient and donor HBV/HCV status. Recipients were classified into four groups: the HBV/HCV coinfected [B+/C+]; HBV mono-infected [B+/C-]; HCV mono-infected [B-/C+]; and hepatitis uninfected [B-/C-]. Kaplan-Meier methods were used to calculate liver graft survival rates, Cox proportional hazard models were used to estimate the effect of hepatitis virus infection, and adjusted for potential confounders. Graft survival rates were highest with B+/C-: 85.3% 1-year survival and 63.0% 10-year survival. Graft survival with B+/C+ was superior to survival with B-/C+: 83.5% 1-year survival and 53.6% 10-year survival vs. B-/C+: 82.9% 1-year survival and 46.1% 10-year survival. Survival with B-/C-: 83.6% 1-year survival and 56.6% 10-year survival was superior to survival with B+/C+ (shown above). After adjustment for confounders, and with the coinfected as reference, B-/C+ recipients had a higher risk of graft loss (hazard ratio, 1.35; 95% CI, 1.10-1.66); the other two groups had a lower risk. Our results suggested-despite reports to the contrary-statistically better graft outcomes with HBV/HCV coinfection than with HCV mono-infection.

Transplantation Journal, 2012

Transplant International, 2012

PLoS ONE, 2013

Objective: The effect of smoking cessation on the risk of diabetes has been reported previously. ... more Objective: The effect of smoking cessation on the risk of diabetes has been reported previously. However, it is unknown whether the association is influenced by weight gain and other potential risk factors.

Journal of Diabetes Science and Technology, 2014

Numerous diabetes-management systems and programs for improving glycemic control to meet guidelin... more Numerous diabetes-management systems and programs for improving glycemic control to meet guideline targets have been proposed, using IT technology. But all of them allow only limited-or no-real-time interaction between patients and the system in terms of system response to patient input; few studies have effectively assessed the systems' usability and feasibility to determine how well patients understand and can adopt the technology involved. DialBetics is composed of 4 modules: (1) data transmission module, (2) evaluation module, (3) communication module, and (4) dietary evaluation module. A 3-month randomized study was designed to assess the safety and usability of a remote health-data monitoring system, and especially its impact on modifying patient lifestyles to improve diabetes self-management and, thus, clinical outcomes. Fifty-four type 2 diabetes patients were randomly divided into 2 groups, 27 in the DialBetics group and 27 in the non-DialBetics control group. HbA1c and fasting blood sugar (FBS) values declined significantly in the DialBetics group: HbA1c decreased an average of 0.4% (from 7.1 ± 1.0% to 6.7 ± 0.7%) compared with an average increase of 0.1% in the non-DialBetics group (from 7.0 ± 0.9% to 7.1 ± 1.1%) (P = .015); The DialBetics group FBS decreased an average of 5.5 mg/dl compared with a non-DialBetics group average increase of 16.9 mg/dl (P = .019). BMI improvement-although not statistically significant because of the small sample size-was greater in the DialBetics group. DialBetics was shown to be a feasible and an effective tool for improving HbA1c by providing patients with real-time support based on their measurements and inputs.

Journal of Diabetes Science and Technology, 2012

Healthcare providers lack the time to provide the continuous life-style education necessary for d... more Healthcare providers lack the time to provide the continuous life-style education necessary for diabetes patients to gain enough skill in diabetes selfmanagement. We developed a real-time, partially automated interactive smartphone-based system (DialBetics)-combining IT and "natural language processing"-to interpret patients' blood glucose, blood pressure, weight, exercise, and dietary content calculated from a message and photo of a meal sent by patients, and respond with communication of findings and advice, achieving diabetes selfmanagement. We examined safety, usability, and impact of a remote health-data monitoring and education system on self-management. Five patients with type 2 diabetes were recruited for a one-month feasibility study. The patients were provided with smartphone, glucometer, blood pressure monitor, pedometer, and weight scale. Patients' measurements were automatically transmitted to a server; exercise and diet information with a meal photo were sent by patients. Patients had excellent compliance for measurements; patients' interest in, and willingness to make, life-style changes improved by receiving real-time findings and advice from DialBetics. Considering the four-week time period of this intervention, results are encouraging in improving self-management. We also plan to assess the impact of DialBetics on patient HbA1c outcomes.

In patients with end-stage chronic kidney disease (CKD) and type 1 diabetes mellitus (DM 1), simu... more In patients with end-stage chronic kidney disease (CKD) and type 1 diabetes mellitus (DM 1), simultaneous pancreas-kidney (SPK) transplantation is currently considered the gold standard therapy. The aim of this study was to analyze and report the long-term clinical outcomes of the 23 SPK transplantations performed at our institution over an 84-month period (January 1, 2000 to December 31, 2006. A prospective analysis of these patients included donor, recipient, and transplantation characteristics. The only requirements for transplantation were blood group compatibility and a negative cross-match. Bladder drainage via pancreaticoduodenocystostomy was performed in all of the patients. Due to a pulmonary embolus 1 patient (4.3%) died at 2 months. The actuarial patient survival rates at 3 months and 1, 3, and 5 years were 95.6%. Causes for the renal graft loss were chronic allograft nephropathy in 3 cases (13%) and death of the patient in 1 case (4.3%). The actuarial censored renal allograft survival rates at 3 months and at 1 year were 100%, and at 3 and 5 years were 91.3%. Causes for the renal graft loss were chronic rejection in 1 case (4.3%) and patient death in 1 case (4.3%). The actuarial censored pancreatic allograft survival rates at 3 months and at 1 and 3 years were 100%, and at 5 years was 95.6%. The results of this work add further evidence that SPK is the gold standard therapy for selected patients with end-stage CKD due to DM 1.