Asthma and Memory Function in Children.

Importance: Asthma is a chronic respiratory disease affecting approximately 5 million children in the US. Rodent models of asthma indicate memory deficits, but little is known about whether asthma alters children's memory development.

Objective: To assess whether childhood asthma is associated with lower memory abilities in children.

Design, setting, and participants: This cohort study used observational data from the Adolescent Brain Cognitive Development (ABCD) Study, a multisite longitudinal investigation that began enrollment in 2015. Approximately 11 800 children aged 9 to 10 years were enrolled at baseline with follow-up at 1 and 2 years. Participants were selected based on exposures described subsequently to determine longitudinal and cross-sectional associations between asthma and memory. Data were analyzed from Month year to Month year.

Exposures: Asthma was determined from parent reports. For the longitudinal analysis, children were selected if they had asthma at baseline and at the 2-year follow-up (earlier childhood onset), at the 2-year follow-up only (later childhood onset), or no history of asthma. For the cross-sectional analysis, children were selected if they had asthma at any time point, or no history of asthma. The comparison group of children with asthma history was matched on demographic and health covariates for each analysis.

Main outcomes and measures: The primary outcome was episodic memory. Secondary outcomes included processing speed, inhibition and attention.

Results: Four hundred seventy-four children were included in the longitudinal analysis (earlier childhood onset: 135 children; mean [SD] age, 9.90 [0.63] years; 76 [56%] male; 53 [28%] Black, 29 [21%] Hispanic or Latino, and 91 [48%] White; later childhood onset: 102 children; mean [SD] age 9.88 [0.59] years; 54 [53%] female; 22 [17%] Black, 19 [19%] Hispanic or Latino, and 83 [63%] White; comparison: 237 children; mean [SD] age, 9.89 [0.59] years; 121 [51%] male; 47 [15%] Black, 48 [20%] Hispanic or Latino, and 194 [62%] White). Children with earlier onset of asthma exhibited lower rates of longitudinal memory improvements relative to the comparison group (β = -0.17; 95% CI, -0.28 to -0.05; P = .01). Two thousand sixty-two children were selected for the cross-sectional analysis (with asthma: 1031 children; mean [SD] age, 11.99 [0.66] years; 588 [57%] male; 360 [27%] Black, 186 [18%] Hispanic or Latino, and 719 [54%] White; without asthma: 1031 children; mean [SD] age 12.00 [0.66] years; 477 [54%] female; 273 [21%] Black, 242 [23%] Hispanic or Latino, and 782 [59%] White). Children with asthma (1031 children) showed lower scores on episodic memory (β = -0.09; 95% CI, -0.18 to -0.01; P = .04), processing speed (β = -0.13; 95% CI, -0.22 to -0.03; P = .01), and inhibition and attention (β = -0.11; 95% CI, -0.21 to -0.02; P = .02).

Conclusions and relevance: In this cohort study, asthma was associated with memory difficulties in children, which may be more severe if asthma onset is earlier in childhood and may extend to executive function abilities.