Condition, prevalence, incidence and trend direction — pediatric persistent asthma home monitoring

1. Summary

The domain dossier already establishes current-asthma prevalence and racial disparity from one 2010-2021 NHIS-based analysis and a persistent/intermittent severity split from a 2006-2010 BRFSS figure; this report's job was the dossier's stated gap — incidence, and a second look at trend direction and geographic concentration. A pooled analysis of nine US birth cohorts (n=6,283 children, 1980-2017) found a crude childhood asthma incidence rate of 27.5 per 1,000 person-years, highest among children aged 0-4 [1]. A separate NCHS-compiled analysis of 2003-2019 national survey data found overall current-asthma prevalence among children under 18 rose from 8.5% (2003) to a peak of 9.6% (2009) before declining to 7.0% (2019) [2], a rise-then-fall shape consistent in direction, though not in exact years or magnitude, with the dossier's own NHIS-based finding of a 2010-2021 decline [3]. A national inpatient-sample analysis found pediatric asthma hospitalizations declined from 2012 through 2020, with the rate of decline itself slowing between the two sub-periods studied [5], and a second, geographically-focused inpatient-sample analysis found rural pediatric acute-asthma hospitalizations carried higher odds of ventilation and longer stays than urban ones despite occurring less often as a share of all rural pediatric admissions [6]. No US-specific incidence rate, prevalence trend, or persistent-severity breakdown broken out for the 5-17 persistent-asthma population specifically was found; every quantity above describes the broader "current asthma" population this domain dossier already flags as distinct from its target population.

2. What Changed

_Baseline (v1). No prior version; this establishes the starting point for future diffs._

3. Details

Incidence — the dossier's stated gap, now filled

The domain dossier's section 1 explicitly recorded incidence as "not searched." One pooled analysis fills that gap directly: nine US birth cohorts spanning 1980-2017 were combined into a single population (n=6,283 children; 55% European American, 25.5% African American, 9.5% Mexican-Hispanic American, 8.5% Caribbean-Hispanic American), following children for an average of 10.4 years (65,291 total person-years) and counting the earliest parental report of a doctor diagnosis of asthma. The pooled crude incidence rate was 27.5 new diagnoses per 1,000 person-years (95% CI 26.3-28.8; 1,789 diagnoses) [1] [single-source]. Rates were highest among children aged 0-4, particularly from 1995 to 1999, with declines beginning first among European American and Mexican-Hispanic American children (2000-2004) and later among African American and Caribbean-Hispanic American children (2010-2014); rates were similar and higher in African American and Caribbean-Hispanic American children than in the other two groups, and a parental history of asthma was associated with a statistically significant rate increase [1] [single-source]. This is a diagnosis-incidence rate across the full pediatric age range studied by these cohorts, not an incidence rate confined to persistent-severity asthma or to ages 5-17 specifically, and it predates 2017.

Trend direction — two national-survey series that agree in shape, not in exact magnitude or years

An NCHS-compiled analysis of national survey data spanning 2003-2019 found overall current-asthma prevalence among children under 18 was 8.5% in 2003, rose to 9.6% in 2009, and fell to 7.0% by 2019, with disparities by sex (males 9.9% vs. females 7.5%), age (ages 10-17, 10.4%, versus ages 0-4, 5.3%), insurance (Medicaid 11.2% vs. privately insured 7.7% vs. uninsured 6.1%), poverty (below the federal poverty level, 11.3%, versus above 400% of it, 7.1%), and race (Black children 14.3%, White 7.6%, Asian 5.4%) reported across that period [2] [single-source]. The domain dossier's own NHIS-based source separately reports current-asthma prevalence "decreased among children from 2010 through 2021" (P=.03 for both the 2010-2017 and 2017-2021 slope segments) [3]. Both series describe a decline in the most recent decade studied, but they are not treated here as two independent corroborating sources: both draw on the same underlying NCHS/NHIS federal survey program, re-analyzed by different research teams over overlapping but non-identical year ranges (2003-2019 vs. 2010-2021), so agreement in direction is recorded, not agreement as independent replication.

A third, NHANES-based (not NHIS/NCHS-derived) cross-sectional trend analysis of US adolescents aged 12-19 (2001-2023, n=17,096 adolescents including 3,290 with current asthma) found no statistically significant narrowing of the Black-white current-asthma prevalence gap after 2012 (2.17 percentage points in 2013-2016 vs. 3.99 percentage points in 2021-2023, P>.05) and no detectable improvement in self-reported poor-control indicators — asthma attacks and emergency-department visits — over the full study period; a sensitivity analysis excluding the 2017-2020 cycle to address COVID-19-related data disruption confirmed the same pattern [4] [single-source]. This is the one genuinely independent (different survey instrument) national source located this pass, and it complicates a simple "improving" reading of the decline reported above: overall prevalence direction and disparity/control direction are not the same finding, and this source addresses only the latter, for adolescents specifically rather than the full 5-17 population.

Hospitalization trend and geographic concentration

A 2012-2020 National Inpatient Sample analysis (already partly used in the domain dossier for its race-specific hospitalization rates) additionally reports that "the number of pediatric asthma hospitalizations decreased over the analysis period," with a meta-regression slope of -0.83 (95% CI -1.14 to -0.52) for 2012-2015 and a shallower -0.35 (95% CI -0.58 to -0.12) for 2016-2019 (2020 data were excluded from the regression, and the analysis was split around a 2015 diagnostic-coding change) [5] [single-source]. A separate 2016-2021 National Inpatient Sample analysis, addressing the dossier's stated gap in state/metro-level detail with a rural-urban comparison instead, found acute asthma accounted for a smaller share of all rural pediatric hospitalizations than of urban ones (0.8% vs. 1.2%, n=64,686 total pediatric acute-asthma discharges aged 2-17) but that rural encounters carried higher odds of requiring ventilation (odds ratio 1.63, 95% CI 1.34-1.98) and longer length of stay (incidence risk ratio 1.08, 95% CI 1.05-1.11) than urban encounters, while generating significantly lower total costs (-$262.09, 95% CI -$332.46 to -$191.73) [6] [single-source]. Read together, these describe a national hospitalization count that is falling, with a residual severity gap by geography among the children who are still hospitalized — not a finding about outpatient home-monitoring behavior.

What remains unresolved

Two gaps the domain dossier already named were searched again this pass and remain open. First, no source located gives a persistent-versus-intermittent severity breakdown for children more recent than the dossier's own 2006-2010 BRFSS-derived 60.3%-persistent figure; none of the six sources in this report reports a severity split at all. Second, no US federal source reporting an absolute current-asthma headcount for children (the "4.8 million / 6.7% / 2023" figure the dossier could not independently verify) was retrievable this pass: cdc.gov's asthma-data pages returned HTTP 403 to both WebFetch and a curl request carrying a browser user-agent, archive.cdc.gov's mirror returned HTTP 404, and the restoredcdc.org mirror of the same page also returned HTTP 403. This is recorded as not retrieved, not not found — a WebSearch snippet surfaced text consistent with that figure, but per this report's sourcing rule a search result is never a source of record, and the primary document behind it could not be opened.

4. Sources

[1] Pediatric asthma incidence rates in the United States from 1980 to 2017 — The Journal of Allergy and Clinical Immunology (published 2021-11, day not given in the PubMed record; accessed 2026-09-01). PMID 33964299 — https://pubmed.ncbi.nlm.nih.gov/33964299/ [peer-reviewed] [2] Epidemiology of Current Asthma in Children Under 18: A Two-Decade Overview Using National Center for Health Statistics (NCHS) Data — Cureus (published 2023-11, day not given in the PubMed record; accessed 2026-09-01). PMID 38143602 — https://pubmed.ncbi.nlm.nih.gov/38143602/ [peer-reviewed] [3] The Status of Asthma in the United States — Preventing Chronic Disease (published 2024-07-18; accessed 2026-09-01). PMID 39025120 — https://pubmed.ncbi.nlm.nih.gov/39025120/ [peer-reviewed] [4] Prevalence and control of asthma among US youths aged 12 to 19 years (2001-2023): A cross-sectional study — Medicine (published 2026-06-26; accessed 2026-09-01). PMID 42363470 — https://pubmed.ncbi.nlm.nih.gov/42363470/ [peer-reviewed] [5] Trends in US Pediatric Asthma Hospitalizations, by Race and Ethnicity, 2012-2020 — Preventing Chronic Disease (published 2024-09-19; accessed 2026-09-01). PMID 39298796 — https://pubmed.ncbi.nlm.nih.gov/39298796/ [peer-reviewed] [6] Rural-Urban Differences in Pediatric Asthma Presentation and Outcomes, 2016-2021 — Hospital Pediatrics (published 2026-08-01; accessed 2026-09-01). PMID 42409379 — https://pubmed.ncbi.nlm.nih.gov/42409379/ [peer-reviewed]

5. Sourcing & Gaps

Well established: Nothing in this report reaches two genuinely independent (different survey instrument) sources reporting the same quantity. The closest approach is the direction-only agreement between [2] and [3] on a post-2009/2010 decline in current-asthma prevalence among children, and that agreement is explicitly not treated as independent replication because both draw on the same underlying NCHS/NHIS federal surveillance program — see section 3.

Thin: Every specific quantity in this report — the pooled incidence rate [1], the 2003-2019 NCHS prevalence series and its subgroup breakdowns [2], the adolescent disparity-persistence finding [4], the 2012-2020 hospitalization meta-regression slopes [5], and the 2016-2021 rural-urban hospitalization comparison [6] — rests on one source apiece and carries its own [single-source] marker in section 3.

Rescoped from class 3: None. Every proposition in this report is a published measured quantity — an incidence rate, a prevalence percentage, a trend slope, an odds ratio, or a cost difference — reported in a citable peer-reviewed document; no question about what a person or clinician would do was posed this pass.

Out of scope: Non-US studies were not pursued as standalone findings. HCPCS/CPT-coded claims-based incidence figures were not pursued, consistent with this repo's standing treatment of CPT descriptors as AMA-licensed and out of scope for an unattended pass.

Not searched vs. not found: Not found — a persistent-versus-intermittent severity breakdown more recent than the domain dossier's own 2006-2010 BRFSS figure, searched for directly this pass and not located in any of the six sources retrieved or in the queries run to find them; a US federal source giving an absolute current-asthma headcount for children, which is recorded as not retrieved (cdc.gov, archive.cdc.gov and restoredcdc.org all returned HTTP 403/404 this pass) rather than not found, since the figure may well exist and simply could not be opened from here. Not searched — state-level (as distinct from rural/urban) prevalence variation; any incidence rate specific to ages 5-17 or to persistent-severity asthma; any trend analysis published after the 2019 (NCHS) or 2021 (NHIS) data years already covered above.

[inference] The direction-only agreement between [2] and [3] on a post-2009/2010 decline is presented in this report as consistent, not as corroborating, given their shared NCHS/NHIS lineage; treating it as two-source corroboration would overstate independence that this report could not confirm from the abstracts alone. Whether the incidence rate in [1] (which ends in 2017 and pools children across a wide age and calendar-year range) is still representative of new pediatric asthma diagnoses today is this report's own open question, not a finding of [1] itself.

6. Claim Candidates