Implementing text-messaging to support and enhance delivery of health behavior change interventions in low- to middle-income countries: case study of the Lifestyle Africa intervention.

The prevalence of non-communicable diseases, such as diabetes and cardiovascular disease, is rising in low- and middle-income countries (LMICs). Health behavior change (HBC) interventions such as the widely used Diabetes Prevention Program (DPP) are effective at reducing chronic disease risk, but have not been adapted for LMICs. Leveraging mobile health (mHealth) technology such as text messaging (SMS) to enhance reach and participant engagement with these interventions has great promise, yet we lack evidence-informed approaches to guide the integration of SMS specifically to support HBC interventions in LMIC contexts. To address this gap, we integrated guidance from the mHealth literature with expertise and first-hand experience to establish specific development steps for building and implementing SMS systems to support HBC programming in LMICs. Specifically, we provide real-world examples of each development step by describing our experience in designing and delivering an SMS system to support a culturally-adapted DPP designed for delivery in South Africa. We outline eight key SMS development steps, including: 1) determining if SMS is appropriate; 2) developing system architecture and programming; 3) developing theory-based messages; 4) developing SMS technology; 5) addressing international SMS delivery; 6) testing; 7) system training and technical support; and 8) cost considerations. We discuss lessons learned and extractable principles that may be of use to other mHealth and HBC researchers working in similar LMIC contexts.Trial registration Clinicaltrials.gov, NCT03342274 . Registered 10 November 2017.

Cost-effectiveness of Lifestyle Africa: an adaptation of the diabetes prevention programme for delivery by community health workers in urban South Africa.

BACKGROUND: Lifestyle Africa is an adapted version of the Diabetes Prevention Program designed for delivery by community health workers to socioeconomically disadvantaged populations in low- and middle-income countries (LMICs). Results from the Lifestyle Africa trial conducted in an under-resourced community in South Africa indicated that the programme had a significant effect on reducing haemoglobin A1c (HbA1c). OBJECTIVE: To estimate the cost of implementation and the cost-effectiveness (in cost per point reduction in HbA1c) of the Lifestyle Africa programme to inform decision-makers of the resources required and the value of this intervention. METHODS: Interviews were held with project administrators to identify the activities and resources required to implement the intervention. A direct-measure micro-costing approach was used to determine the number of units and unit cost for each resource. The incremental cost per one point improvement in HbA1c was calculated. RESULTS: The intervention equated to 71 United States dollars (USD) in implementation costs per participant and a 0.26 improvement in HbA1c per participant. CONCLUSIONS: Lifestyle Africa reduced HbA1c for relatively little cost and holds promise for addressing chronic disease in LMIC. Decision-makers should consider the comparative clinical effectiveness and cost-effectiveness of this intervention when making resource allocation decisions. TRIAL REGISTRATION: Trial registration is at ClinicalTrials.gov (NCT03342274).

Single- and cross-commodity discounting among adults who use alcohol and cannabis: Associations with tobacco use and clinical indicators.

BACKGROUND: Delay discounting assessments typically involve choices between an immediate outcome and a larger amount of the same outcome after a delay. Real-world choices, however, more often involve qualitatively different alternatives. The primary aim of this study was to examine single- and cross-commodity discounting of money, alcohol, and cannabis, along with clinical measures of alcohol and cannabis use among people who use both alcohol and cannabis, yet differ in tobacco cigarette smoking status (i.e., dual- versus tri-use). METHODS: An online crowdsourced sample (N = 318) of people who reported using alcohol and cannabis in the past week completed single- and cross-commodity discounting assessments across each combination of money, alcohol, and cannabis. We recruited a balanced number of people who did and did not also use tobacco cigarettes and examined associations between discounting, tobacco use, and clinical indicators. RESULTS: People who reported using tobacco cigarettes in addition to alcohol and cannabis tended to engage in significantly higher rates of harmful alcohol and cannabis use than those who reported using only alcohol and cannabis. Cross-commodity discounting was significantly associated with patterns of harmful alcohol and cannabis use while no associations emerged for single-commodity discounting. CONCLUSIONS: Cross-commodity discounting provides a nuanced account of intertemporal choice by incorporating relative commodity valuation and appears to characterize harmful alcohol and cannabis use more clearly than single-commodity arrangements. Further cross-commodity research is needed to better understand the interplay between temporal location and relative commodity value among people who use multiple substances.

Differential mechanisms of change in motivational interviewing versus health education for smoking cessation induction.

Objective: To determine if Motivational Interviewing (MI) versus health education (HE) elicited different types of client language and whether these differences were associated with outcomes in a randomized clinical trial (RCT) for cessation induction among people who smoke with low motivation to quit. Methods: A secondary data analysis was conducted using data from the MI and HE arms of a trial in which people who smoke (N = 202) with low desire to quit were randomly assigned to four sessions of MI, HE or brief advice. Mediation analyses examined two types of client language: change talk (CT) and a novel form of client speech called "learning talk" (LT). Outcomes were assessed at baseline, 3 and 6 months. Results: With HE as the reference group, MI resulted in greater CT (OR = 3.0, 95% CI: 1.7-5.5) which was associated with better outcomes (average d = .34, SD = .13) and HE resulted in greater LT (OR = .05, 95% CI: .02-.10) which was also associated with better outcomes (average d = .42, SD = .08). Indirect parallel mediation effects on quit attempts were significant for both MI-CT (OR = 1.4, 95% CI: 1.1-1.7) and HE-LT (OR = .4, 95% CI: .2-.7). Conclusions: MI and HE were both efficacious via different pathways to change, confirming the utility of MI in this RCT as well as highlighting the potential of HE based on the "5R's" for smoking cessation. These findings emphasize the value of exploring theorized mechanisms of action of interventions evaluated in RCTs. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Functional brain activation changes associated with practice in delaying smoking among moderate to heavy smokers: study protocol and rationale of a randomized trial (COPE).

BACKGROUND: Most smokers struggle to overcome tobacco addiction. Neuroscientific models of addiction emphasize the importance of brain regions associated with cognitive control and reward to understand the cycle of addiction and relapse. During an attempt at abstinence, the cognitive control system appears to be underpowered to override the heightened reward system of the addicted brain. Thus, one neural target for treatment is to strengthen the cognitive control system. It may be possible to improve the functioning of the cognitive control system via deliberate practice. METHODS/DESIGN: This study will determine the effects of practicing delaying smoking on brain and behavioral measures of cognitive control. Smoking patterns will be monitored for 1 week and then smokers (N = 80) will be randomized to either practice cognitive control by delaying their first cigarette of the day for 2 weeks (practice group) or they will continue monitoring only (no practice group). Functional magnetic resonance imaging will be performed while smokers regulate their responses to smoking images (i) at baseline and (ii) after 2 weeks of practice (or no practice). DISCUSSION: The primary aim of this study will be to identify the impact of practicing cognitive control on functional brain activation changes in response to smoking cues. If successful, this project will establish a neurobiological biomarker for increasing cognitive control and demonstrate the feasibility of neuroimaging methods to predict the efficacy of an intervention without a large clinical trial. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03080844 . Registered March 15, 2017.

Adolescents' behavioral and neural responses to e-cigarette advertising.

Although adolescents are a group heavily targeted by the e-cigarette industry, research in cue-reactivity has not previously examined adolescents' behavioral and neural responses to e-cigarette advertising. This study addressed this gap through two experiments. In Experiment One, adult traditional cigarette smokers (n = 41) and non-smokers (n = 41) answered questions about e-cigarette and neutral advertising images. The 40 e-cigarette advertising images that most increased desire to use the product were matched to 40 neutral advertising images with similar content. In Experiment Two, the 80 advertising images selected in Experiment One were presented to adolescents (n = 30) during an functional magnetic resonance imaging brain scan. There was a range of traditional cigarette smoking across the sample with some adolescents engaging in daily smoking and others who had never smoked. Adolescents self-reported that viewing the e-cigarette advertising images increased their desire to smoke. Additionally, all participants regardless of smoking statuses showed significantly greater brain activation to e-cigarette advertisements in areas associated with cognitive control (left middle frontal gyrus), reward (right medial frontal gyrus), visual processing/attention (left lingual gyrus/fusiform gyrus, right inferior parietal lobule, left posterior cingulate, left angular gyrus) and memory (right parahippocampus, left insula). Further, an exploratory analysis showed that compared with age-matched non-smokers (n = 7), adolescent smokers (n = 7) displayed significantly greater neural activation to e-cigarette advertising images in the left inferior temporal gyrus/fusiform gyrus, compared with their responses to neutral advertising images. Overall, participants' brain responses to e-cigarette advertisements suggest a need to further investigate the long-run impact of e-cigarette advertising on adolescents.

Executive function fails to predict smoking outcomes in a clinical trial to motivate smokers to quit.

BACKGROUND: Executive function (EF) is considered an important mediator of health outcomes. It is hypothesized that those with better EF are more likely to succeed in turning their intentions into actual health behaviors. Prior studies indicate EF is associated with smoking cessation. Experimental and longitudinal studies, however, have yielded mixed results. Few studies have examined whether EF predicts post-treatment smoking behavior. Fewer still have done so prospectively in a large trial. We sought to determine if EF predicts quit attempts and cessation among community smokers in a large randomized trial evaluating the efficacy of motivational interventions for encouraging cessation. METHODS: Participants (N=255) completed a baseline assessment that included a cognitive battery to assess EF (Oral Trail Making Test B, Stroop, Controlled Oral Word Association Test). Participants were then randomized to 4 sessions of Motivational Interviewing or Health Education or one session of Brief Advice to quit. Quit attempts and cessation were assessed at weeks 12 and 26. RESULTS: In regression analyses, none of the EF measures were statistically significant predictors of quit attempts or cessation (all ps>0.20). CONCLUSIONS: Our data did not support models of health behavior that emphasize EF as a mediator of health outcomes. Methodological shortcomings weaken the existing support for an association between EF and smoking behavior. We suggest methodological improvements that could help move this potentially important area of research forward.

Pramipexole enhances disadvantageous decision-making: Lack of relation to changes in phasic dopamine release.

Pramipexole (PPX) is a high-affinity D2-like dopamine receptor agonist, used in the treatment of Parkinson's disease (PD) and restless leg syndrome. Recent evidence indicates that PPX increases the risk of problem gambling and impulse-control disorders in vulnerable patients. Although the molecular bases of these complications remain unclear, several authors have theorized that PPX may increase risk propensity by activating presynaptic dopamine receptors in the mesolimbic system, resulting in the reduction of dopamine release in the nucleus accumbens (NAcc). To test this possibility, we subjected rats to a probability-discounting task specifically designed to capture the response to disadvantageous options. PPX enhanced disadvantageous decision-making at a dose (0.3 mg/kg/day, SC) that reduced phasic dopamine release in the NAcc. To test whether these modifications in dopamine efflux were responsible for the observed neuroeconomic deficits, PPX was administered in combination with the monoamine-depleting agent reserpine (RES), at a low dose (1 mg/kg/day, SC) that did not affect baseline locomotor and operant responses. Contrary to our predictions, RES surprisingly exacerbated the effects of PPX on disadvantageous decision-making, even though it failed to augment PPX-induced decreases in phasic dopamine release. These results collectively suggest that PPX impairs the discounting of probabilistic losses and that the enhancement in risk-taking behaviors secondary to this drug may be dissociated from dynamic changes in mesolimbic dopamine release.

Flash rate discrimination in rats: rate bisection and generalization peak shift.

Two experiments were conducted to determine whether responding by albino rats can be brought under the stimulus control of different flash rates. In the first experiment, a conditional discrimination procedure was employed whereby two different flash rates (fast or slow) signaled the availability of reinforcement on one of two levers (left or right). Stimulus control emerged rapidly and improved with continued training. When intermediate flash rates were presented during probe sessions, the bisection point of the fast and slow flash rates was near their geometric mean, consistent with research employing other stimulus types. In the second experiment, a successive discrimination procedure was employed whereby responding in the presence of one flash rate (S(+) ) was reinforced while responding in the presence of another flash rate (S(-) ) was not reinforced. Again, stimulus control emerged quickly and improved with continued training. Test sessions in which many different flash rates were presented for brief periods in extinction revealed the peak shift phenomenon, in which peak response rates are shifted from the S(+) in a direction away from the S(-) . Flash rate is endorsed as a continuous stimulus dimension that is useful for differentially signaling schedule components.

Immediate postsession feeding reduces operant responding in rats.

Three experiments investigated the effects of immediate and delayed postsession feeding on progressive-ratio and variable-interval schedule performance in rats. During Experiments 1 and 2, immediate postsession feeding decreased the breakpoint, or largest completed ratio, under progressive-ratio schedules. Experiment 3 was conducted to extend the results of the first two experiments to responding maintained by variable-interval schedules with different session lengths (15 and 60 min). Response rates decreased in all 4 subjects when postsession feeding immediately followed a 15-min session and in 3 of 4 subjects when postsession feeding immediately followed a 60-min session. The implications of this research are twofold: (1) The functional context in which within-session reinforcers are embedded extends outside the experimental chamber, and (2) supplemental postsession feedings should be sufficiently delayed from the end of a session to avoid weakening operant behavior in the experimental sessions.

Response acquisition with signaled delayed reinforcement in a rodent model of ADHD.

Previous research by Hand et al. [10] showed that acquisition of lever pressing was retarded in spontaneously hypertensive rats (SHRs) relative to Wistar-Kyoto rats (WKYs) when unsignaled delays of 15s separated lever presses from food delivery. The SHRs took longer to begin responding, exhibited a slower increase in response rates, responded at a lower asymptotic response rate and earned fewer reinforcers than the WKYs. The present experiment examined whether similar strain differences in acquisition would be observed if the same delay to reinforcement was signaled. Signaled delays of reinforcement typically result in lesser disruption of steady-state operant behavior than unsignaled delays, presumably because the signals function as conditioned reinforcers. Under a response-acquisition procedure, signals might be expected to facilitate acquisition which could minimize SHR-WKY strain differences. The present study exposed SHR and WKY rats to a procedure where a single lever press illuminated the houselight and delivered a food pellet 15s later. Response acquisition was similar between SHR and WKY rats under 15-s signaled delays of reinforcement; the responses emitted, delay resets and pellets earned by both strains were similar. Removal of the delay signal immediately decreased responding for both strains with the SHRs showing a significantly slower recovery over time. Overall the results suggest that signals occurring during response-reinforcer delays can mitigate the response-weakening effects of delayed reinforcement in a rodent model of ADHD.

Differential effects of d-amphetamine on impulsive choice in spontaneously hypertensive and Wistar-Kyoto rats.

The spontaneously hypertensive rat (SHR) has been shown to exhibit three of the behavioral characteristics of attention-deficit/hyperactivity disorder: hyperactivity, attention deficit and impulsivity. This study used SHRs and a control strain to assess the effects of the commonly prescribed psychomotor stimulant, d-amphetamine, on impulsivity, defined as choice for a small, immediate over a large, delayed reinforcer. d-Amphetamine (1.0, 3.2 and 5.6 mg/kg) was administered to SHR and Wistar-Kyoto rats (WKY; their progenitor strain) before sessions of a choice task involving small, immediate and larger, delayed food reinforcers. As reported earlier, SHRs were more impulsive than WKYs (they preferred the smaller, immediate reinforcer). d-Amphetamine had no effect on preference for the SHRs, but increased choices for the small, immediate reinforcer for the WKYs at the 1.0 and 3.2 doses. Thus, d-amphetamine did not reduce impulsivity in the already impulsive SHRs, but did increase impulsivity in rats that were not already impulsive.

Evaluating timing in spontaneously hypertensive and Wistar-Kyoto rats using the peak procedure.

A core deficit in timing may underlie the symptoms of attention-deficit/hyperactivity disorder (ADHD). Timing deficits have been observed in ADHD-diagnosed children but have yet to be fully explored in the spontaneously hypertensive rat (SHR), a purported model of ADHD. We asked whether SHRs demonstrate ADHD-like timing deficits using the peak procedure. Response rates across peak intervals were modeled using the sum of two Gaussian curves. Results showed that SHRs peaked earlier than Wistar-Kyotos based on 4s intervals that contained the individuals' maximum response rates but not based on model parameters. The strains showed approximately equal precision of timing based on Weber fractions derived from model parameters, a result that replicates previous findings and does not support the use of SHRs to model this aspect of ADHD.

Impulsive choice in a rodent model of attention-deficit/hyperactivity disorder.

The spontaneously hypertensive rat (SHR) has been studied extensively as a purported rodent model of attention-deficit/hyperactivity disorder (ADHD). Because ADHD in humans is partially defined by marked impulsivity, SHRs, if a valid model of ADHD, ought to behave more impulsively than their normotensive parent strain, Wistar Kyoto (WKY). This prediction was evaluated in two experiments that employed an intertemporal choice procedure in which SHRs and WKYs made repeated choices between a single food pellet delivered immediately and three food pellets delivered after a delay. Four or five delays were investigated (1, 3, 6, 12 and 24s); the experiments differed in the manner in which the delays were experienced. In Experiment 1, the delay values changed after each session and were presented in ascending then descending order. SHRs chose more small/immediate reinforcers than WKYs at the longest delays during the ascending series and at nearly all delays during the descending series. In Experiment 2, the delay values remained in effect for several sessions and were presented in random order. Again, the SHRs chose more small/immediate reinforcers than the WKYs at the longest delays. Thus, in the present study, the SHRs were shown to be more impulsive than the WKYs as defined by preference for smaller, immediate reinforcers over larger, delayed ones in an intertemporal choice procedure.

Response acquisition with delayed reinforcement in a rodent model of attention-deficit/hyperactivity disorder (ADHD).

The spontaneously hypertensive rat (SHR) has been shown to exhibit behavioral characteristics analogous to those exhibited by humans diagnosed with attention-deficit/hyperactivity disorder (ADHD). The present study was conducted to further evaluate the validity of the SHR model of ADHD by characterizing learning of a novel response under conditions of delayed reinforcement. Seven experimentally naïve SHRs and a control group of seven normotensive Wistar-Kyoto (WKY) rats were exposed to a contingency where one lever press initiated pellet delivery after a 15-s, resetting delay. Rats in both groups acquired lever pressing, and the pattern of acquisition was well described with a three-parameter, sigmoidal equation. Response acquisition was retarded in the SHRs; they took longer to acquire the behavior, exhibited lower response rates and earned fewer reinforcers over the course of the experiment. When reinforcer delivery was made immediate in a subsequent condition, the SHRs exhibited higher response rates than the WKY, suggesting that the lower rates of responding seen in the SHRs were due to the reinforcer delay. The results replicate previous research on response acquisition with delayed reinforcement and provide further validation of the SHR strain as a model of ADHD. Like humans diagnosed with ADHD, the SHRs appear to be hypersensitive to delayed consequences, which in the present context, interfered with learning a novel behavior.