Showing papers by "David S. Ludwig published in 2016"

Ontological Choices and the Value-Free Ideal

Abstract: The aim of this article is to argue that ontological choices in scientific practice undermine common formulations of the value-free ideal in science. First, I argue that the truth values of scientific statements depend on ontological choices. For example, statements about entities such as species, race, memory, intelligence, depression, or obesity are true or false relative to the choice of a biological, psychological, or medical ontology. Second, I show that ontological choices often depend on non-epistemic values. On the basis of these premises, I argue that it is often neither possible nor desirable to evaluate scientific statements independently of non-epistemic values. Finally, I suggest that considerations of ontological choices do not only challenge the value-free ideal but also help to specify positive roles of non-epistemic values in an often neglected area of scientific practice.

Lifespan Weighed Down by Diet.

Abstract: This Viewpoint discusses the possibility that declines in life expectancy from obesity-related chronic disease could reverse decades-long improvements in mortality trends, and proposes clinical and policy responses.

Creating an integrated care model for childhood obesity: a randomized pilot study utilizing telehealth in a community primary care setting

Abstract: Summary In an integrated care model, involving primary care providers (PCPs) and obesity specialists, telehealth may be useful for overcoming barriers to treating childhood obesity. We conducted a pilot study comparing body mass index (BMI) changes between two arms (i) PCP in-person clinic visits plus obesity specialist tele-visits ( PCP visits + specialist tele-visits) and (ii) PCP in-person clinic visits only ( PCP visits only), with ongoing tele-consultation between PCPs and obesity specialists for both arms. Patients (N = 40, 10–17 years, BMI ≥ 95th percentile) were randomized to Group 1 or 2. Both groups had PCP visits every 3 months for 12 months. Using a cross-over protocol, Group 1 had PCP visits + specialist tele-visits during the first 6 months and PCP visits only during the second 6 months, and Group 2 followed the opposite sequence. Each of 12 tele-visits was conducted by a dietitian or psychologist with a patient and parent. Retention rates were 90% at 6 months and 80% at 12 months. BMI (z-score) decreased more for Group 1 (started with PCP visits + specialist tele-visits) vs. Group 2 (started with PCP visits only) at 3 months (−0.11 vs. −0.05, P = 0.049) following frequent tele-visits. At 6 months (primary outcome), BMI was lower than baseline within Group 1 (−0.11, P = 0.0006) but not Group 2 (−0.06, P = 0.08); however, decrease in BMI at 6 months did not differ between groups. After crossover, BMI remained lower than baseline for Group 1 and dropped below baseline for Group 2. An integrated care model utilizing telehealth holds promise for treating children with obesity.

Lowering the Bar on the Low-Fat Diet

Abstract: The recent revelation that the sugar industry attempted to manipulate science in the 1960s1 has once again focused attention on the quality of the scientific evidence in the field of nutrition and how best to prevent diet-related chronic disease. Beginning in the 1970s, the US government and major professional nutrition organizations recommended that individuals in the United States eat a low-fat/high-carbohydrate diet, launching arguably the largest public health experiment in history. Throughout the ensuing 40 years, the prevalence of obesity and diabetes increased several-fold, even as the proportion of fat in the US diet decreased by 25%. Recognizing new evidence that consumption of processed carbohydrates—white bread, white rice, chips, crackers, cookies, and sugary drinks—but not total fat has contributed importantly to these epidemics, the 2015 USDA Dietary Guidelines for Americans essentially eliminated the upper limit on dietary fat intake.2 However, a comprehensive examination of this massive public health failure has not been conducted. Consequently, significant harms persist, with the low-fat diet remaining entrenched in public consciousness and food policy. In addition, critical scientific questions have been muddled.

A randomized pilot study of dietary treatments for polycystic ovary syndrome in adolescents.

Abstract: Summary Background Evidence is lacking to recommend one diet over another when treating polycystic ovary syndrome (PCOS). Objectives To obtain preliminary data, comparing the impact of a low-glycaemic load (LGL) vs. low-fat (LF) diet on biochemical hyperandrogenism in overweight and obese adolescents with PCOS. To ascertain feasibility of recruiting study participants, in partnership with an adolescent clinic, and implementing dietary interventions. Methods Randomized controlled trial of 19 overweight and obese adolescents with PCOS and not using hormonal contraceptives (HCs). Interventions comprised nutrition education, dietary counselling and cooking workshops to foster adherence to a LGL (45% carbohydrate, 35% fat, 20% protein) or LF (55% carbohydrate, 25% fat, 20% protein) diet over 6 months. Serum bioavailable testosterone was the primary outcome. Results Sixteen (LGL, n = 7; LF, n = 9) participants completed the study. Body fat percentage decreased (P < 0.05) in response to the interventions, with no difference between the LGL and LF groups (−1.2% vs. −2.2%; P = 0.16). Bioavailable testosterone did not change for either group (−0.4 vs. −1.8 ng dL−1; P = 0.35). Regarding feasibility, recruiting adolescents posed a challenge, and use of HCs was a main reason for ineligibility. Participants attended 5.9 of 6 in-person visits and 2.6 of 3 cooking workshops, completed 4.9 of 6 telephone counselling calls, and reported high satisfaction with the diets and cooking workshops (≥8 on a 10-cm scale). Conclusions Dietary interventions were beneficial for weight control but did not attenuate biochemical hyperandrogenism. Innovative strategies are needed to recruit adolescents for studies aimed at assessing independent effects of diet on features of PCOS.

Physical changes in the home environment to reduce television viewing and sugar-sweetened beverage consumption among 5- to 12-year-old children: a randomized pilot study.

Abstract: This study evaluated the feasibility of a home-based intervention to reduce sugar-sweetened beverage intake and television viewing among children. Lower income parents of overweight children aged 5-12 years (n = 40) were randomized to a home environment intervention to reduce television viewing with locking devices and displace availability of sugar-sweetened beverages with home delivery of non-caloric beverages (n = 25), or to a no-intervention control group (n = 15) for 6 months. Data were collected at baseline and 6 months. After 6 months, television viewing hours per day was significantly lower in the intervention group compared with the control group (1.7 [SE = .02] vs. 2.6 [SE = .25] hours/day, respectively, P < .01). Sugar-sweetened beverage intake was marginally significantly lower among intervention group compared to control group children (0.21 [SE = .09] vs. 0.45 [SE = .10], respectively, P < .09). Body mass index (BMI) z-score was not significantly lower among intervention compared to control children. Among a lower income sample of children, a home-based intervention reduced television viewing, but not sugar-sweetened beverage intake or BMI z-score.

Outcomes from an orientation model to reduce attrition in paediatric weight management

Abstract: Summary We aimed to reduce attrition of newly referred patients in a paediatric weight management programme by implementing an orientation to address families’ expectations and screen for and support behavioural and mental health problems and psychosocial stressors at programme outset. Orientation impact was monitored with run charts with percentages of scheduled encounters completed. Long-term impact was assessed by comparing patients in the initial 6 months of the orientation to a baseline group of referred patients during the same 6-month time interval in the prior year (Pre-Orientation Group). The outcome measure was programme attrition within 15 months. Groups were compared using Kaplan–Meier survival analysis and Cox proportional hazards regression modelling. Patients in the Orientation Group had a 23% increased odds of attrition compared to patients in the Pre-Orientation group (adjusted Hazard ratio, aHR 1.23; 95% confidence interval, CI: 1.01, 1.51) and shorter median duration of follow-up (2.0 vs. 2.9 months, P = 0.004). An increase in body mass index z-score of 1 unit resulted in a nearly fivefold increased odds of attrition (aHR 5.24; 95% CI: 2.95, 9.3). An orientation for new patients did not reduce attrition within 15 months. We suggest that ongoing retention strategies should be embedded into the treatment phase of the programme.