Preventable chronic diseases continue to drive health care costs substantially and importantly upward, in part due to a lack of sustainable treatment options. Specific medications, such as cholesterol-lowering and diabetes medications target mostly one chronic disease-associated abnormality of elevated LDL cholesterol or plasma glucose, respectively, rather than the cause of the abnormality. While surgical interventions successfully treat obesity and a spectrum of associated metabolic changes, they poorly address the behavioral and lifestyle-related factors that led to the development of chronic conditions in the first place. In contrast, comprehensive lifestyle interventions may result in multiple physiological systems changes including behavior modifications that support long-term healthier lifestyle choices [5, 29].
Here, we report findings that a tri-pronged lifestyle intervention consisting of diet, physical activity and stress management improves disease-associated markers of participants with multiple chronic conditions. All measured biometric and laboratory variables significantly improved after just 6 weeks of intervention. Beneficial changes in blood pressure and glucose were observed in many participants by the second week of the program, thus supporting previously reported observations of the quick onset of measurable benefits that follow a comprehensive lifestyle intervention . Serum HDL cholesterol decrease after 6 weeks was most likely associated with early weight loss, as reported . Nevertheless, reductions in total cholesterol are more profound than in HDL cholesterol, resulting in improved ratio of total cholesterol to HDL cholesterol, an established risk factor for coronary artery disease . Although HDL cholesterol generally decreases during weight loss, it increases following weight maintenance in proportion to the amount of weight that is lost [32, 33]. At week 30, HDL cholesterol is significantly higher than at the baseline and the total cholesterol/HDL ratio improves further. Fasting triglyceride level is also significantly reduced at both points in time (week 6 and 30) compared with baseline, reflecting the observations that triglycerides improve after weight loss . Fasting hypertriglyceridemia is an established risk factor for cardiovascular disease and may predict disease progression . In addition, TG/HDL ratio, a possible powerful predictor of extensive coronary artery disease is also improved, that is, decreased significantly . In our study, we did not examine if these beneficial changes lead to better cardiovascular outcomes. In a comprehensive lifestyle intervention similar to ours, where a low-fat plant-based diet rather then a Mediterranean-style diet was used, reductions in total and LDL cholesterol were of greater magnitude than in this study and were associated with the arrest and/or reversal of coronary artery disease [5, 37].
A large proportion of the global burden of chronic diseases, particularly cardiovascular disease, obesity and some cancers, involves non-resolving, chronic inflammation . Lifestyle 180 intervention resulted in significantly healthier markers of glucose metabolism and inflammation (Table 6). Although measurements of insulin and US-CRP were initiated at later stages of the program and data were available for smaller number of participants, these results show large percentage decreases, strengthening the evidence that these lifestyle interventions may be used as anti-inflammatory therapies to treat insulin resistance, beneficially impact metabolic syndrome and associated chronic diseases . It is, therefore, not surprising that the percent of participants with metabolic syndrome was significantly lower after 6 months of lifestyle interventions (an estimated relative 32 percent lower, from 54% to 37%).
Here we report only the outcomes for those participants who had biometric and lab measurements. These participants had greater lowering of mean weight and cholesterol at week 6 than those who did not attend this follow up. Thus, it is likely that those who witnessed greater early successes in their outcomes were more motivated to remain engaged in the program. We were unable to obtain biometric and laboratory measurements of patients who dropped out at 6 months, but the observed differences at 6 weeks suggest that those patients who dropped out at 6 months may have done so because their outcomes were not as good as for those who remained. At six months, 30-43% attrition rate (laboratory data and biometrics, respectively) was comparable to some lifestyle intervention programs, but lower than in others [40–42]. More than 75% of participants who enrolled into the program were selected by their employers on the basis that they had at least one of the chronic conditions and frequently included those who made little health improvements after participating in standard disease management programs. No pre-enrollment evaluation was conducted to ascertain whether potential participants were considering making lifestyle changes and whether they could count on support of their spouses and families. Local self-insured employers paid in full the costs of the program for their participants (with exception of 26 participants who paid 20% of the costs). Participants were not penalized if they missed the classes and no financial incentives (besides paying for the program itself) were provided to them to attend the classes. It is possible that the attendance at week 30 follow up would have been better if some of these factors were considered and follow up visits were more frequent, as evidenced by changes to the program (for example, shorter Immersion phase of 4 weeks instead of original 6 weeks has decreased spacing between the visits, the longest being now 2 months instead of 3 months) we made (our subsequent data not reported here). Adherence to lifestyle interventions seems to increase with multiple follow-up visits .
This study has several weaknesses. Pre-post type of study is not suitable to establish causality and assess how much of the observed changes are specifically due to the program. A randomized clinical trial would be needed for that purpose. However, implementation of a comprehensive lifestyle intervention in a randomized fashion is hampered by preferences of participants (those who prefer to engage in lifestyle improvement activities and those who don't) and may suffer from crossover problems . Some of the observed changes could have been due to the placebo effect and possibly some other unidentified factors, not just to the participation in the lifestyle program per se.
Less than 25% of participants paid out of their pocket for participation in the program. This self-selected group of people who could financially afford the program and were able to accommodate their schedules during the first six weeks of the Immersion Phase are clearly not representative of the general population. For example, personality traits differ between obese persons who enroll and those who do not enroll in comprehensive lifestyle intervention programs . Also, there was a bias in selection of participants by their employers to enroll in Lifestyle 180 as discussed above.
Because of only 6 months of intervention, inferences about long-term effectiveness cannot be made. Longer term data are needed to demonstrate that beneficial lifestyle changes are sustainable for such a large percentage of participants. An additional weakness of this study is that we did not evaluate adherence to the program and therefore we were unable to correlate the degree of adherence to the lifestyle program with changes in risk factors and to identify aspect(s) of lifestyle changes that are the most important for good outcomes. The outcomes data are reported for a heterogeneous group of participants and a subgroup analysis would be needed for better evaluation of chronic disease-specific outcomes. In addition, one might argue that significant improvements in lipids, glucose and inflammation markers could be the result of increased use of medications rather than participation in lifestyle intervention. While the cost-effectiveness analysis of the Lifestyle 180 program (including changes in pharmaceuticals) is in progress (manuscript in preparation), as shown in Table 8, for every newly started medication or one with increased dose, 3.3 medications were stopped, reduced in dose or avoided. This suggests that a spectrum of significant and beneficial biometric and biomarker improvements occurred among participants who used less, not more medications.