Recent Secular Trends of Body Mass Index in Individuals With Bipolar Disorders and in the General Population.

OBJECTIVE: The aims of this study were to investigate secular trends and distribution of body mass index (BMI) among individuals with bipolar disorders and the general population between 2008 and 2019. METHODS: Data were from the Swedish National Quality Register for Bipolar Disorder, where 24,423 adults with bipolar disorders were identified, and from the national Swedish Living Conditions Surveys, where 77,485 adults from the general population were identified. Quantile regression was used to compare the 15th, 50th, and 85th percentiles of BMI across age and study years. RESULTS: The study sample included 22,127 individuals with bipolar disorders (mean age, 48 years; 63% women) and 71,894 individuals from the general population (mean age, 52 years; 51% women). BMI percentiles were higher among individuals with bipolar disorders. At the 50th percentile, the BMI group differences were 1.1 (95% CI=0.8-1.14) for men and 1.8 (95% CI=1.5-2.1) for women. The gap was widest at the 85th BMI percentile: men, 2.3 (95% CI=1.8-2.8); women, 4.1 (95% CI=3.7-4.6). BMI increased over time in both study groups, but more in the group with bipolar disorders. The changes per decade in mean BMI were 0.4 (95% CI=0.3-0.5) among men in the general population, 1.1 (95% CI=0.7-1.4) among men with bipolar disorders, 0.6 (95% CI=0.5-0.7) among women in the general population, and 1.4 (95% CI=1.1-1.7) among women with bipolar disorders. Women with bipolar disorders had the highest prevalence and the greatest rate of increase of obesity. In 2019, the obesity prevalence was 33% among women and 29% among men with bipolar disorders, compared with 13% and 15%, respectively, among women and men in the general population. CONCLUSIONS: Adults with bipolar disorders had a higher BMI and a higher prevalence of obesity than the general population, indicating a higher cardiometabolic risk. Annually, BMI increased more in the group with bipolar disorders than in the general population, particularly among women and among those with high BMI.

Cardiometabolic risk indicators in individuals with bipolar disorders: a replication study.

OBJECTIVES: We recently conducted the first longitudinal study comparing cardiometabolic risk indicators (CMRIs) between a cohort of individuals with bipolar disorders (BDs) and controls from the general population. Here, we sought to validate the findings in that study using an independent case-control sample. METHODS: We used data from the St. Göran project's Gothenburg cohort. The BDs group and the control group were examined at baseline and after a median of eight and seven years, respectively. Data collection occurred between March 2009 and June 2022. We used multiple imputation to handle missing data and linear mixed effects model to examine the annual change in CMRIs over the study period. RESULTS: The baseline cohort included 407 individuals with BDs (mean age 40 years, 63% women) and 56 controls (mean age 43 years, 54% women). Of those, 63 persons with BDs and 42 controls participated at follow-up. At baseline, individuals with BDs had significantly higher mean values of body mass index (ß = 0.14, p = 0.003) than controls. Over the study period, the difference in average annual change between the patient and the control group indicated an increase in patients relative to controls in waist-to-hip ratio (0.004 unit/year, p = 0.01), diastolic (0.6 mm Hg/year, p = 0.048), and systolic (0.8 mm Hg/year, p = 0.02) blood pressure. CONCLUSIONS: This study replicated the main findings from our previous study and showed that central obesity and measures of blood pressure worsened over a relatively short time in individuals with BDs relative to controls. It is vital for clinicians to monitor CMRIs in persons with BDs and to be proactive in preventing cardiometabolic diseases in this high-risk group.

Time effect on cardiometabolic risk indicators in patients with bipolar disorder: a longitudinal case-control study.

Individuals with bipolar disorder are at increased risk for cardiovascular diseases. Most studies have described increases in cardiometabolic risk indicators (CMRIs) using clinical cut-off values. Further, there are no longitudinal studies on CMRIs. We aimed to investigate continuous measures of CMRIs in individuals with bipolar disorder and controls using both cross-sectional and longitudinal data. We used data from the Swedish St. Göran Bipolar project. Study individuals were examined at baseline and after a median of 6 and 7 years for the control and patient group, respectively. Data were collected December 2005-December 2020. The cohort included 281 individuals with bipolar disorder (mean age 39 years, 59% women) and 114 controls (mean age 38 years, 55% women). Of those, 155 patients and 74 controls also provided follow-up data. At baseline, individuals with bipolar disorder had significantly higher mean values of waist-to-hip ratio (WHR) (ß = 0.142, p = 0.001), body mass index (ß = 0.150, p = 0.006), plasma triacylglycerol (TAG) (ß = 0.218, p < 0.001), total/plasma high-density lipoprotein-cholesterol (TChol/HDL-C) ratio (ß = 0.103, p = 0.03), TAG/HDL-C ratio (ß = 0.151, p = 0.006), and non-HDL-C (ß = 0.168, p = 0.001) than controls. Most CMRIs remained higher in the patient group at follow-up. The difference between patients and controls increased over time for WHR (0.005 unit/year, p < 0.001), and systolic (1.1 mm Hg/year, p = 0.002) and diastolic (0.8 mm Hg/year, p < 0.001) blood pressure. Individuals with bipolar disorder displayed persistently higher levels of nearly all included CMRIs. Over time, a subset of CMRIs worsened in patients relative to controls. This suggests that active measures to counter cardiovascular risk in persons with bipolar disorder should be considered.