which对吗？

Obesity prevalence has been increasing for centuries, and obesity as a disease is now accepted to be a global epidemic.The rate of increase is also accelerating, with estimates suggesting global prevalence has doubled between 1980 and 2017, now being approximately 5% of children and 12% of all adults.3 There are wide variations between different countries, with obesity prevalence in both adults and children being generally higher in areas with a higher sociodemographic index (SDI), which incorporates, among other factors, per capita income and educational attainment.3 However, in some demographic groups, for example young men, the most rapid increase in obesity is occurring in countries with low-middle SDI, and in most areas the rate of increase of obesity prevalence in children is greater than in adults.The burden of disease associated with these changes is massive, accounting for an estimated 4 million deaths globally in 2015.3 Cardiovascular disease and diabetes account for the majority of obesity-related deaths, but its contribution to respiratory disease is also important. Obesity increases the likelihood of developing several respiratory diseases, for the multiple reasons described below. Respiratory symptoms such as dyspnoea and a reduced breath-hold time are also more common in obese subjects, even in the absence of respiratory disease, as a result of the physiological challenges of severe obesity.

几个世纪以来，肥胖的患病率一直在上升，现已认为是一种全球的流行病。肥胖增长率也在加速，据估计，全球患病率在1980年至2017年间翻了一番，现在约占儿童的5%，约占成年人的12%³。不同国家间差异很大，在社会人口统计的指数(sociodemographic index，SDI)较高的地区，成人和儿童的肥胖患病率普遍较高，高SDI地区，个人收入和教育程度也高。然而，在某些人口群体中（例如年轻男性），肥胖患病率增长最快的国家是中低SDI的国家，在大多数地区，儿童肥胖症患病率的增长率大于成人。与肥胖的患病率增长相关的疾病负担巨大，2015年全球估计400万人死亡与肥胖相关，心血管疾病和糖尿病占肥胖相关死亡的大多数，但其对呼吸道疾病的影响也很重要。肥胖可能会增加几种呼吸系统疾病的发生率，原因如下。即使没有呼吸道疾病，由于重度肥胖造成的严重生理限制，呼吸困难和屏气时间缩短等呼吸道症状也很常见。

which理解的对吗？

these changes啥意思，就是“Obesity prevalence has been increasing for centuries”？