Effects of Caffeine on Exercise Responses and Performance in Children and Youth

Limited caffeine consumption as first-line treatment in managing primary monosymptomatic enuresis in children: how effective is it? A randomised clinical trial

OBJECTIVE

Evidence about the negative caffeine effect on enuresis in children remains understudied or poorly understood. The study aimed to investigate the effect of caffeine restriction on the improvement and severity of primary monosymptomatic nocturnal enuresis (PMNE).

DESIGN

Randomised clinical trial.

SETTING

Two referral hospitals in Tehran, Iran, from 2021 to 2023.

PATIENTS

Five hundred and thirty-four PMNE children aged 6-15 years (each group 267).

INTERVENTIONS

Amount of caffeine consumption was recorded by the feed frequency questionnaire and was estimated by Nutrition 4 software. Caffeine consumption per day in the intervention group was <30 mg, and in the control group, 80-110 mg. All children were asked to return 1 month later to check the recorded data. The ordinal logistic regression analysis was used to assay the effects of caffeine restriction on PMNE by relative risk (RR) at a 95% CI.

MAIN OUTCOME MEASURES

The effect of limited caffeine consumption on the improvement and severity of PMNE.

RESULTS

The mean age of the intervention and control groups was 10.9±2.3 and 10.5±2.5 years, respectively. The mean number of bed-wetting before caffeine restriction in the intervention and control group was 3.5 (SD 1.7) times/week and 3.4 (SD 1.9) times/week (p=0.91) and 1 month after intervention were 2.3 (SD 1.8) times/week and 3.2 (SD 1.9) times/week, respectively (p=0.001). Caffeine restriction significantly reduced the severity of enuresis in the intervention group. Fifty-four children (20.2%) improved (dry at night) in caffeine restriction and 18 children (6.7%) in the control group with RR 0.615 at 95% CI 0.521 to 0.726, p=0.001. The caffeine restriction significantly reduced the enuresis in children with a number-needed-to-treat benefit 7.417. It means you must treat 7.417 PMNE children with caffeine limitation to improve one child with enuresis (become dry).

CONCLUSION

Caffeine restriction can be helpful in reducing PMNE or its severity. Constructive limitation of caffeine is suggested as one of the first-line treatments in the management of PMNE.

TRIAL REGISTRATION NUMBER

IRCT20180401039167N3.

Investigation of potential behavioral and physiological effects of caffeine on D. magna

With the ever-increasing consumption of pharmaceutical compounds, their presence in the environment is now an undisputable reality. The majority of these compounds are released into the wild after their therapeutic use, as biotransformation products or in their original form. The presence of this class of compounds in the environment, due to their biological properties, can exert effects on non-target organisms, with adverse consequences. In addition, some bioactive substances, such as stimulants of the central nervous system, are also used by humans as part of their diet. The adverse consequences posed by such chemicals may be permanent or transient, if the exposure to xenobiotics is halted; it is thus of the paramount importance to study effects that result from long-term exposure to toxicants, but also the recovery of organisms previously exposed to such substances, especially if such chemicals may cause some type of addiction. Caffeine (1,3,7-trimethylxanthine) is a naturally occurring alkaloid found in many plants, being one of the most common stimulant/pharmaceutical compounds found in the environment. In addition, it is addictive, and strongly consumed by humans, a factor that contributes also for its continuous presence in the aquatic environment. The aim of this study was to evaluate the effects of environmentally relevant concentrations (0.08; 0.4; 2; 10; and 50 μg/L) of caffeine on behavior and physiological parameters (that are proxies of metabolic traits, such as oxygen uptake and glycogen content), in individuals of the freshwater crustacean species Daphnia magna, of distinct ages, and with or without a recovery period in the absence of caffeine. Regarding behavior, the results indicated that caffeine exposure altered the moved distance of the test organisms, but not according to a coherent pattern; low concentrations of caffeine reduced the movement of exposed daphnids, while higher levels did not have any measurable effect on this parameter. In addition, it was possible to identify subtle withdrawal effects (animals exposed to caffeine during 21 days and kept in uncontaminated media for 2 days). Regarding the other two studied parameters, caffeine exposure did not result in any significant modification in oxygen uptake and glycogen stores/reserves of the test organisms, in animals continuously exposed, or in those subjected to a recovery period, suggesting that despite a behavioral stimulatory effect, this was not followed by any metabolic change, and no addictive effect was possible to infer. The results showed that the presence of caffeine in environmental concentrations can induce mild behavioral effects at low, albeit realistic levels, but not capable of establishing clear biochemical changes.