Serum Concentrations of 25-Hydroxyvitamin D and Depression in a General Middle-Aged to Elderly Population in Finland.

OBJECTIVES: Low concentrations of serum 25-hydroxyvitamin D [25(OH)D] have been postulated to associate with an increased prevalence of depression. As there are a limited number of publications on this issue, we examined the association between serum 25(OH)D and depression in a general middle-aged or older population. DESIGN: A population-based cross-sectional study. SETTING AND PARTICIPANTS: A total of 1602 men and women from the population-based Kuopio Ischaemic Heart Disease Risk Factor Study (KIHD) in Eastern Finland, aged 53-73 y in 1998-2001, were analysed. MEASUREMENTS: Depressive symptoms were assessed with the DSM-III depression scale, and those individuals who had scores over 4 (range 0-12) or had reported undergoing current antidepressant therapy, were considered as suffering from depression. Associations were estimated in serum 25(OH)D tertiles using logistic regression. RESULTS: Among the participants, 183 subjects (11.4%) were considered to have depression. The mean age of the subjects was 62.6 years (SD 6.4, range 53.4-73.8 years). The mean serum 25(OH)D concentration was 43.8 nmol/L (SD 17.7, range 8.5-112.8 nmol/L), concentrations <50 nmol/L were observed in 65.0% of the subjects, and only 5.0% displayed concentrations ≥75 nmol/L. After multivariable adjustments, the odds ratios for having depression in the tertiles (from highest to the lowest) of serum 25(OH)D were 1, 1.35 (95 % CI: 0.87, 2.09) and 1.64 (95 % CI: 1.03, 2.59), P for trend=0.036. CONCLUSION: These findings indicate that a lower concentration of serum 25(OH)D is associated with a higher prevalence of depression in an elderly general population.

Sample selection may bias the outcome of an adolescent mental health survey: results from a five-year follow-up of 4171 adolescents.

OBJECTIVES: The representativeness of the data is one of the main issues in evaluating the significance of research findings. Dropping out is common in adolescent mental health research, and may distort the results. Nevertheless, very little is known about the types of systematic bias that may affect studies in a) the informed consent phase and b) later in follow-up phases. STUDY DESIGN: The authors addressed this gap in knowledge in a five-year follow-up study on a sample of adolescents aged 13-18 years. METHODS: The data were collected using self-report questionnaires. The baseline sample consisted of 4171 adolescents, 1827 (43.8%) of whom gave consent to be contacted for a follow-up survey, but only 797 (19.1%) participated in the follow-up. Binary logistic regression models were used to explain the participation. RESULTS: Young age, female gender, a high number of hobbies, good performance at school in the native language and general subjects, family disintegration such as divorce, high parental employment, and symptoms of depression and anxiety were associated with both consent and participation. However, the effect of mental health aspects was smaller than the effect of age and gender. CONCLUSIONS: This study confirmed the possibility of systematic selection bias by adolescents' sociodemographic characteristics. The representativeness of the study sample might have been improved by more intense recruitment strategies.

How does lifestyle intervention affect depressive symptoms? Results from the Finnish Diabetes Prevention Study.

AIMS: To assess the effect of lifestyle intervention on depressive symptoms during a 36-month randomized clinical trial designed to prevent Type 2 diabetes. METHODS: A total of 522 middle-aged participants, who were overweight or obese and had impaired glucose tolerance, were randomized to the lifestyle intervention or control group in the Finnish Diabetes Prevention Study. The intervention group received individualized counselling aimed at reducing weight and increasing physical activity. Depressive symptoms were measured using the Beck Depression Inventory among a subgroup of 140 participants. RESULTS: On study entry, the mean Beck Depression Inventory scores ± sd were 6.8 ± 5.6 in the intervention group and 6.7 ± 5.5 in the control group. Beck Depression Inventory scores reduced during the intervention study: the mean ± sd (95% CI) reduction was 0.90 ± 4.54 (-1.99 to -0.19) scores in the intervention group and 0.75 ± 4.47 (-1.80 to 0.31) in the control group, with no difference between the groups. In a stepwise linear multivariate regression analysis, the variables with the strongest associations with the change in Beck Depression Inventory scores were baseline Beck Depression Inventory scores, marital status, weight change and change of total energy intake (R(2) = 0.209, P < 0.001). CONCLUSIONS: Participation in the study lowered depression scores, with no specific group effect. Among the lifestyle changes, particularly successful reduction of body weight was associated with the greater reduction of depressive symptoms. Thus, regardless of the intensity of the treatment, the success in executing alterations in one's lifestyle and behaviour is associated with beneficial changes in mood.

Serum adiponectin and resistin levels in major depressive disorder.

OBJECTIVE: To examine the role of the adipose-tissue-derived low-grade inflammation markers adiponectin and resistin in major depressive disorder (MDD) in a population-based sample. METHOD: Serum levels of adiponectin and resistin were measured from 70 DSM-IV MDD subjects and 70 healthy controls. Depression severity was assessed with the 29-item Hamilton Depression Rating Scale. RESULTS: The MDD group had lowered serum adiponectin levels. Regression modelling with adjustments for age, gender, overweight, several socioeconomic and lifestyle factors, coronary heart disease and metabolic syndrome showed that each 5.0 microg/ml decrease in serum adiponectin increased the likelihood of MDD by approximately 20% (P = 0.01). The resistin levels correlated with atypical (P = 0.02), but not with typical depressive symptoms (P = 0.12). CONCLUSION: Our findings suggest that the lowered adiponectin levels in MDD are depression-specific and not explained by conventional low adiponectin-related factors such as such as coronary heart disease and metabolic disorders.

Association of depressive symptoms and metabolic syndrome in men.

OBJECTIVE: To explore the relationship between several indicators of depression and metabolic syndrome (MetS). METHOD: A population-based sample with high (HMS group) or low (LMS group) levels of mental symptoms, including those of depression, in three follow-ups participated in a clinical examination in 2005 (n = 223). MetS was determined according to the NCEP criteria. RESULTS: The prevalence of MetS was 49% in men and 21% in women. Men with MetS had higher rates of major depressive disorder than other men. They also displayed higher Hamilton Rating Scale for Depression (HDRS) scores and more often signs of suicidality. In logistic regression analyses, higher HDRS scores (OR 1.31, 95% CI 1.04-1.64) and belonging to the HMS group (OR 10.1, 95% CI 1.98-51.3) were independent associates for MetS but only in men. CONCLUSION: The results highlight that there is an association between long-term depressive symptoms and the emergence of MetS, especially in men.

Low maximal oxygen uptake is associated with elevated depressive symptoms in middle-aged men.

A low level of physical activity has been associated with depression, and increased physical activity has been found to have a positive effect on mood. However, the association between maximal oxygen uptake (VO(2max)) and mood has been poorly studied. In this study VO(2max) (ml/kg per min) was measured in a sample of 1,519 men aged 46-61 years during a cycle ergometer test by using respiratory gas exchange. Men with a history of psychiatric disorder or serious physical illness were excluded. Depressive symptoms were assessed using the 18-item Human Population Laboratory Depression Scale (HPL). Those who scored 5 or more in the HPL were considered to have elevated depressive symptoms. The participants were classified into quartiles according to the VO(2max). Those in the lowest quartile had a more than 3-fold (OR: 3.42; 95% CI: 1.65-7.09; p < 0.001) higher risk of having elevated depressive symptoms compared with those in the highest quartile, even after adjusting for several confounders (OR: 3.38; 95% CI: 1.60-7.14; p < 0.001). In conclusion, low VO(2max) is associated with having elevated depressive symptoms in middle-aged men.