Gender differences in the association between tooth loss and obesity among older adults in Brazil

OBJECTIVE To analyze if differences according to gender exists in the association between tooth loss and obesity among older adults.METHODS We analyzed data on 1,704 older adults (60 years and over) from the baseline of a prospective cohort study conducted in Florianopolis, SC, Southern Brazil. Multivariable logistic regression models were used to assess the association between tooth loss and general and central obesity after adjustment for confounders (age, gender, skin color, educational attainment, income, smoking, physical activity, use of dentures, hypertension, and diabetes). Linear regressions were also assessed with body mass index and waist circumference as continuous outcomes. Interaction between gender and tooth loss was further assessed.RESULTS Overall mean body mass index was 28.0 kg/m2. Mean waist circumference was 96.8 cm for males and 92.6 cm for females. Increasing tooth loss was positively associated with increased body mass index and waist circumference after adjustment for confounders. Edentates had 1.4 (95%CI 1.1;1.9) times higher odds of being centrally obese than individuals with a higher number of teeth; however, the association lost significance after adjustment for confounders. In comparison with edentate males, edentate females presented a twofold higher adjusted prevalence of general and central obesity. In the joint effects model, edentate females had a 3.8 (95%CI 2.2;6.6) times higher odds to be centrally obese in comparison with males with more than 10 teeth present in both the arches. Similarly, females with less than 10 teeth in at least one arch had a 2.7 (95%CI 1.6;4.4) times higher odds ratio of having central obesity in comparison with males with more than 10 teeth present in both the arches.CONCLUSIONS Central obesity was more prevalent than general obesity among the older adults. We did not observe any association between general obesity and tooth loss. The association between central obesity and tooth loss depends on gender – females with tooth loss had greater probability of being obese.

研究目的：分析老年人群中牙齿缺失与肥胖的关联是否存在性别差异。
研究方法：本研究基于巴西南部圣卡塔琳娜州弗洛里亚诺波利斯市一项前瞻性队列研究的基线数据，共纳入1704名60岁及以上的老年受试者。采用多变量logistic回归模型，在校正年龄、性别、肤色、受教育程度、收入水平、吸烟情况、体力活动、义齿佩戴情况、高血压及糖尿病等混杂因素后，评估牙齿缺失与全身性肥胖、中心性肥胖的关联；同时以体重指数（body mass index, BMI）和腰围作为连续结局指标，构建线性回归模型进行分析，并进一步检验性别与牙齿缺失的交互作用。
研究结果：研究对象的总体平均体重指数为28.0 kg/m²。男性平均腰围为96.8 cm，女性平均腰围为92.6 cm。校正混杂因素后，牙齿缺失数量越多，体重指数与腰围水平越高。全口无牙受试者发生中心性肥胖的比值比为存留牙齿数量较多者的1.4倍（95%CI：1.1~1.9），但该关联在校正混杂因素后失去统计学显著性。与全口无牙男性相比，全口无牙女性的全身性肥胖与中心性肥胖的校正后患病率高出两倍。在联合效应模型中，与上下颌均存留10颗以上牙齿的男性相比，全口无牙女性发生中心性肥胖的比值比为3.8倍（95%CI：2.2~6.6）；同样，与上下颌均存留10颗以上牙齿的男性相比，至少一侧颌骨存留牙齿不足10颗的女性发生中心性肥胖的比值比为2.7倍（95%CI：1.6~4.4）。
研究结论：本研究人群中，中心性肥胖的患病率高于全身性肥胖。未观察到全身性肥胖与牙齿缺失存在显著关联。中心性肥胖与牙齿缺失的关联存在性别差异——存在牙齿缺失的女性发生肥胖的概率更高。