Prospective association of comorbid hypertension and depressive symptoms with C-reactive protein in older adults

Hypertension and depressive symptoms often occur together in the older population, and each has been separately linked to elevated C-reactive protein (CRP). This study investigated the prospective association between comorbid hypertension and depressive symptoms and high-sensitivity CRP (hs-CRP) in a Chinese older population. This study used data from 4978 participants aged 50 and above, who took part in two waves (2011 and 2015) of the China Health and Retirement Longitudinal Study (CHARLS). Hypertension, depressive symptoms and hs-CRP were measured. Logistic regressions adjusted for confounding variables were used to examine the association between the baseline comorbidity of hypertension and depressive symptoms and the change in hs-CRP levels. Hypertension and depressive symptoms did not show independent associations with an elevated level of hs-CRP. Participants with comorbid hypertension and depressive symptoms were more likely to develop a higher level of hs-CRP at follow-up (OR = 1.39, 95 % CI: 1.12–1.74) even after adjusting for covariates. Sex- and age-stratified analyses indicated that the association between the comorbidity and higher levels of hs-CRP were prone to be observed in women (OR = 1.55, 95 % CI: 1.16–2.08) and older adults (OR = 1.74, 95 % CI: 1.20–2.52). Comorbid hypertension and depressive symptoms is related to a higher risk of elevated hs-CRP levels. This association appears to be more pronounced among women and older adults compared to their counterparts. Depression was self-reported by participants, which might be considered less unreliable than clinical diagnoses.