Saila Loikas - Academia.edu (original) (raw)

Papers by Saila Loikas

Research paper thumbnail of Undiagnosed Diseases in Patients with Dementia – A Potential Target Group for Intervention

Dementia and Geriatric Cognitive Disorders, 2004

To study undiagnosed diseases in older people with and without dementia. Cross-sectional populati... more To study undiagnosed diseases in older people with and without dementia. Cross-sectional population-based study in Lieto, southwestern Finland. All the inhabitants aged 64 and more in Lieto. Participation rate was 82% (n = 1,260). Dementia and its subtypes were diagnosed according to prevailing criteria. Medical conditions were assessed in clinical examinations and from medical records. 112 patients with dementia were found; 66% of them had at least 1 undiagnosed disease compared to 48% of the non-demented group (p = 0.041). The demented subjects had more undiagnosed hypercholesterolaemia (p = 0.039) and undiagnosed hypothyroidism (p = 0.032) than the controls. Undiagnosing is more common among patients with dementia. Screening strategies should be developed further to find these patients.

Research paper thumbnail of Renal impairment compromises the use of total homocysteine and methylmalonic acid but not total vitamin B12 and holotranscobalamin in screening for vitamin B12 deficiency in the aged

Clinical Chemical Laboratory Medicine, 2000

Vitamin B(12) deficiency and renal impairment are common in the aged, and therefore the screening... more Vitamin B(12) deficiency and renal impairment are common in the aged, and therefore the screening test for vitamin B(12) deficiency should not be affected by renal function. Renal impairment has been associated with increased concentrations of plasma total homocysteine and methylmalonic acid, as well as increased total vitamin B(12) and holotranscobalamin concentrations. The effect of renal impairment on vitamin B(12)-related biochemical variables was assessed in 1011 aged subjects. Renal function as indicated by serum cystatin C correlated strongly with plasma total homocysteine (r(s)=0.53, p<0.001) and serum methylmalonic acid (r(s)=0.27, p<0.001), but not with serum total vitamin B(12) (r(s)=-0.04, p=0.227) or holotranscobalamin (r(s)=-0.01, p=0.817). Either total vitamin B(12) or holotranscobalamin rather than homocysteine or methylmalonic acid should be used when screening an aged population prone to renal impairment.

Research paper thumbnail of No bias between the first and the new version of RIA for serum holo-transcobalamin by Axis-Shield

Clinical Chemistry and Laboratory Medicine, 2000

Research paper thumbnail of Vitamin B12 deficiency in the aged: a population-based study

Age and Ageing, 2007

Background: vitamin B12 deficiency is common in the aged, but it is controversial whether only so... more Background: vitamin B12 deficiency is common in the aged, but it is controversial whether only some risk groups should be investigated instead of screening the entire aged population. Objectives: to describe the prevalence of vitamin B12 deficiency in the Finnish aged, and to find out if the subjects especially prone to vitamin B12 deficiency could be identified by the risk factors or clinical correlates. Design: a cross-sectional, population-based study of 1048 aged subjects (age 65-100 years) was carried out. Data on lifestyle factors and clinical conditions were collected, physical examinations were conducted and laboratory variables related to vitamin B12 were measured. Results: vitamin B12 deficiency had been previously diagnosed in 27 (2.6%) subjects, and a laboratory diagnosis (total vitamin B12 <150 pmol/l, or total vitamin B12 150-250 pmol/l and holotranscobalamin 37 pmol/l and homocysteine 15 µmol/l) was made for 97 (9.5%) subjects. Low serum total vitamin B12 (<150 pmol/l) was observed in 6.1% and borderline total vitamin B12 (150-250 pmol/l) in 32% of the subjects. Male gender (OR 1.9, 95% CI 1.2-2.9), age 75 (OR 2.2, 95% CI 1.4-3.4) and refraining from milk products (OR 2.3, 95% CI 1.2-4.4) increased the probability for vitamin B12 deficiency. Anaemia (OR 1.3, 95% CI 0.7-2.3) or macrocytosis (OR 1.2, 95% CI 0.6-2.7) did not predict vitamin B12 deficiency. Conclusion: undiagnosed vitamin B12 deficiency is remarkably common in the aged, but no specific risk group for screening can be identified. Thus, biochemical screening of unselected aged population is justified. General practitioners play a key role in diagnosing early vitamin B12 deficiency.

Research paper thumbnail of RIA for Serum Holo-Transcobalamin: Method Evaluation in the Clinical Laboratory and Reference Interval

Clinical Chemistry, 2003

Background: Decreased serum holo-transcobalamin (holoTC) could be the earliest marker of cobalami... more Background: Decreased serum holo-transcobalamin (holoTC) could be the earliest marker of cobalamin (Cbl) deficiency, but there has been no method suitable for routine use. We evaluated a new commercial holoTC RIA, determined reference values, and assessed holoTC concentrations in relation to other biochemical markers of Cbl deficiency. Methods: The reference population consisted of 303 individuals 22-88 years of age, without disease or medication affecting Cbl or homocysteine metabolism. In elderly individuals (>65 years), normal Cbl status was further confirmed by total homocysteine (tHcy; <19 mol/L) and methylmalonic acid (MMA; <0.28 mol/L) concentrations within established reference intervals. HoloTC in Cbl deficiency was studied in a population of 107 elderly individuals with normal renal function. The Cbl deficiency was graded as potential (total Cbl <150 pmol/L or tHcy >19 mol/L), possible (total Cbl <150 pmol/L and either tHcy >19 mol/L or MMA >0.45 mol/L), and probable (tHcy >19 mol/L and MMA >0.45 mol/L).

Research paper thumbnail of Undiagnosed Diseases in Patients with Dementia – A Potential Target Group for Intervention

Dementia and Geriatric Cognitive Disorders, 2004

To study undiagnosed diseases in older people with and without dementia. Cross-sectional populati... more To study undiagnosed diseases in older people with and without dementia. Cross-sectional population-based study in Lieto, southwestern Finland. All the inhabitants aged 64 and more in Lieto. Participation rate was 82% (n = 1,260). Dementia and its subtypes were diagnosed according to prevailing criteria. Medical conditions were assessed in clinical examinations and from medical records. 112 patients with dementia were found; 66% of them had at least 1 undiagnosed disease compared to 48% of the non-demented group (p = 0.041). The demented subjects had more undiagnosed hypercholesterolaemia (p = 0.039) and undiagnosed hypothyroidism (p = 0.032) than the controls. Undiagnosing is more common among patients with dementia. Screening strategies should be developed further to find these patients.

Research paper thumbnail of Renal impairment compromises the use of total homocysteine and methylmalonic acid but not total vitamin B12 and holotranscobalamin in screening for vitamin B12 deficiency in the aged

Clinical Chemical Laboratory Medicine, 2000

Vitamin B(12) deficiency and renal impairment are common in the aged, and therefore the screening... more Vitamin B(12) deficiency and renal impairment are common in the aged, and therefore the screening test for vitamin B(12) deficiency should not be affected by renal function. Renal impairment has been associated with increased concentrations of plasma total homocysteine and methylmalonic acid, as well as increased total vitamin B(12) and holotranscobalamin concentrations. The effect of renal impairment on vitamin B(12)-related biochemical variables was assessed in 1011 aged subjects. Renal function as indicated by serum cystatin C correlated strongly with plasma total homocysteine (r(s)=0.53, p&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.001) and serum methylmalonic acid (r(s)=0.27, p&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.001), but not with serum total vitamin B(12) (r(s)=-0.04, p=0.227) or holotranscobalamin (r(s)=-0.01, p=0.817). Either total vitamin B(12) or holotranscobalamin rather than homocysteine or methylmalonic acid should be used when screening an aged population prone to renal impairment.

Research paper thumbnail of No bias between the first and the new version of RIA for serum holo-transcobalamin by Axis-Shield

Clinical Chemistry and Laboratory Medicine, 2000

Research paper thumbnail of Vitamin B12 deficiency in the aged: a population-based study

Age and Ageing, 2007

Background: vitamin B12 deficiency is common in the aged, but it is controversial whether only so... more Background: vitamin B12 deficiency is common in the aged, but it is controversial whether only some risk groups should be investigated instead of screening the entire aged population. Objectives: to describe the prevalence of vitamin B12 deficiency in the Finnish aged, and to find out if the subjects especially prone to vitamin B12 deficiency could be identified by the risk factors or clinical correlates. Design: a cross-sectional, population-based study of 1048 aged subjects (age 65-100 years) was carried out. Data on lifestyle factors and clinical conditions were collected, physical examinations were conducted and laboratory variables related to vitamin B12 were measured. Results: vitamin B12 deficiency had been previously diagnosed in 27 (2.6%) subjects, and a laboratory diagnosis (total vitamin B12 <150 pmol/l, or total vitamin B12 150-250 pmol/l and holotranscobalamin 37 pmol/l and homocysteine 15 µmol/l) was made for 97 (9.5%) subjects. Low serum total vitamin B12 (<150 pmol/l) was observed in 6.1% and borderline total vitamin B12 (150-250 pmol/l) in 32% of the subjects. Male gender (OR 1.9, 95% CI 1.2-2.9), age 75 (OR 2.2, 95% CI 1.4-3.4) and refraining from milk products (OR 2.3, 95% CI 1.2-4.4) increased the probability for vitamin B12 deficiency. Anaemia (OR 1.3, 95% CI 0.7-2.3) or macrocytosis (OR 1.2, 95% CI 0.6-2.7) did not predict vitamin B12 deficiency. Conclusion: undiagnosed vitamin B12 deficiency is remarkably common in the aged, but no specific risk group for screening can be identified. Thus, biochemical screening of unselected aged population is justified. General practitioners play a key role in diagnosing early vitamin B12 deficiency.

Research paper thumbnail of RIA for Serum Holo-Transcobalamin: Method Evaluation in the Clinical Laboratory and Reference Interval

Clinical Chemistry, 2003

Background: Decreased serum holo-transcobalamin (holoTC) could be the earliest marker of cobalami... more Background: Decreased serum holo-transcobalamin (holoTC) could be the earliest marker of cobalamin (Cbl) deficiency, but there has been no method suitable for routine use. We evaluated a new commercial holoTC RIA, determined reference values, and assessed holoTC concentrations in relation to other biochemical markers of Cbl deficiency. Methods: The reference population consisted of 303 individuals 22-88 years of age, without disease or medication affecting Cbl or homocysteine metabolism. In elderly individuals (>65 years), normal Cbl status was further confirmed by total homocysteine (tHcy; <19 mol/L) and methylmalonic acid (MMA; <0.28 mol/L) concentrations within established reference intervals. HoloTC in Cbl deficiency was studied in a population of 107 elderly individuals with normal renal function. The Cbl deficiency was graded as potential (total Cbl <150 pmol/L or tHcy >19 mol/L), possible (total Cbl <150 pmol/L and either tHcy >19 mol/L or MMA >0.45 mol/L), and probable (tHcy >19 mol/L and MMA >0.45 mol/L).