Urbanization and prevalence of depression in diabetes

SummaryObjectivesTo depict recent secular trend (2001–2005) in prevalence of depression among diabetic population in Taiwan, and to explore the influences of urbanization on the prevalence of depression.Study designA descriptive correlation study design relating urbanization and prevalence of depression.MethodsAnnual prevalence of depression was calculated as the ratio of number of individuals with depression (ICD-9-CM: 296, 309, or 311) to the size of diabetic population (ICD-9-CM: 250), which were ascertained from ambulatory care claim data of Taiwan’s National Health Insurance between 2001 and 2005. Multivariate Poisson regression analysis was used to assess the secular trend in the prevalence of comorbid depression, and to appraise the influence of urbanization on prevalence of depression in diabetic patients.ResultsThe prevalence of depression among diabetic population increased annually from 22.6/103 in 2001 to 27.0/103 in 2005 with a significantly and linearly rising trend (β = 0.0461, p < 0.0001). Diabetic population living in urban areas showed the largest increase in prevalence (6.3/103), followed by those from rural areas (5.6/103). Compared to the diabetic patients residing in rural areas, those living in urban areas (RR = 1.28, 95% CI = 1.25–1.31) and those from satellite towns (RR = 1.22, 95% CI = 1.19–1.25) both had significantly increased adjusted RR.ConclusionsThere is a significant increasing trend in prevalence of depression among diabetic population in recent years in Taiwan. Diabetic patients from urban areas not only had the greatest prevalence of depression but also showed the largest increase in prevalence during the study period, which highlights a need for managing depression in urban diabetes.