Differing Impact of Weight Cycling on Ambulatory Blood Pressure versus Conventional Blood Pressure Assessment: A Possible Explanation to Controversy

BACKGROUND: Weight cycling (WC) is a widespread behavior associated with elevated laboratory blood pressure (BP). The impact WC may have on ambulatory BP (ABP) is unknown. METHODS: Impact of self-reported WC history on ABP was assessed via cross-sectional nonexperimental design. Sixty-five women completed the Weight and Lifestyle Inventory (WALI) questionnaire. The WALI has been shown to be a reliable index of WC (r=0.87, P<0.001). Data were analyzed looking at WC both as a continuous and criterion variable, and subjects were dichotomized as either WC or non-WC (NWC). RESULTS: WC (n=31) were older (39.7±8.9 vs. 33.1±11.3 years), had a higher percent body fat (47.1%±6.2% vs. 41.4%±7.8%), and were less fit (21.2±5.4 vs. 26.7±7.6 mL/kg/min) than NWC (n=34). No significant correlation between laboratory systolic BP (SBP, P=0.830) or diastolic BP (DBP, P=0.997) and WC was observed. A significant correlation between the number of WC and systolic ABP (r=0.326, P=0.010) and trend for diastolic ABP (r=0.238, P=0.065) was found. SBP (23% vs. 17%, P<0.001) and DBP (13% vs. 9%, P<0.001) load was higher for WC compared to NWC women. CONCLUSION: WC may deleteriously affect BP outcomes that might only be observed when ABP monitoring is used.