The longitudinal relation of inflammation to incidence of vasomotor symptoms

OBJECTIVE: Vasomotor symptoms (VMS), the most frequently reported symptoms during the menopausal transition, have been associated with inflammation. Whether inflammation is a risk factor for or a consequence of VMS remains unclear. The objectives of these analyses were to determine if elevated proinflammatory marker levels were associated with increased incident VMS in women without VMS at baseline and whether these associations varied by menopause transition stage or race/ethnicity. METHODS: We used longitudinal data on incident VMS, high-sensitivity C-reactive protein (hs-CRP; n = 1,922) and interleukin-6 (IL-6; n = 203) from 13 follow-up visits in the Study of Women's Health Across the Nation, which included five racial/ethnic groups of midlife women. We performed multivariable discrete-time survival analyses to determine adjusted hazard ratios (aHRs) for the association of these proinflammatory markers with incident VMS in women without VMS at baseline. RESULTS: We found no significant associations of incident VMS with dichotomized hs-CRP (>3 vs ≤3 mg/L) at baseline, concurrent or prior visit (aHRs, 1.04-2.03) or IL-6 (>1.44 vs ≤1.44 pg/mL) at visit 1, concurrent or prior visit (aHRs, 0.67-1.62), or continuous hs-CRP or IL-6 values over 13 follow-up visits (with nonsignificant adjusted increased hazards ranging from 0% to 2%). CONCLUSIONS: Our results showed no significant association of the proinflammatory biomarkers, hs-CRP or IL-6, either concurrently or with subsequent incident VMS, indicating that inflammation was unlikely to be a risk factor for VMS. Thus, clinical treatments directed at reducing inflammation would be unlikely to reduce the occurrence of VMS.