The Scope of Drinking Opportunity Creation Is Associated with Stronger Habits and Greater Water Intake in Patients with Kidney Stones

Background/Objectives: Kidney stone patients struggle to attain the recommended fluid intake. Prior work has focused on the strength of habits (i.e., context–behavior associations) for fluid intake, but given the variability in the contexts of daily life, the scope of efforts to create opportunities to drink across contexts may also be important. Methods: A cross-sectional study was conducted among adults with a history of kidney stones (N = 265). Participants identified situations in which they made an effort to have a glass of water nearby (opportunity creation), rated the experienced automaticity of water intake (i.e., habit strength, measured via the Self-Report Behavioral Automaticity Index), and reported past-week fluid intake volumes. Latent class analysis was used to identify distinct subgroups based on the contexts in which individuals created opportunities to drink, and multivariable linear regression was used to examine the associations between habit strength, class membership, and daily fluid intake. Results: Three latent classes were identified based on the scope of opportunity creation across contexts: widespread (27.9% of the sample; water intake: 41.2 ± 17.1 fl oz), selective (43.4%; water intake: 32.6 ± 16.33 fl oz), and limited (28.7%; water intake: 19.01 ± 16.08 fl oz). The widespread class reported stronger habits (22.45 ± 6.43) and higher water intake than the selective (19.97 ± 6.20) or limited classes (14.38 ± 6.81) (all Ps < 0.001). Stronger habits significantly predicted higher daily water intake (b = 0.90, SE = 0.16, p < 0.001). No significant association was found between habit strength and total fluid intake volume (b = 1.06, SE = 0.74, p = 0.17). Conclusions: Habit strength positively predicted water intake for all classes. To increase fluid intake, clinical interventions should help patients develop drinking habits tied to specific daily contexts.