Research report
A research report is the sourced material a domain
dossier is synthesized from — generated on a plan and a cadence, one topic per file.
A report carries no confidence tags. Its bracketed markers say who might have
an incentive to shade a line; none of them says anyone checked it. To reach a score, a line has
to be drafted onto a candidate as unverified and pass the Verifier or the
Corroborator, like everything else.
Section epidemiology · Version 2026-09-01 · Cadence annual · Evidence class 2 published · Sources 7 · Supersedes none
Domain: internal-hemorrhoids-office-based-treatment · Scope: Public primary sources reachable by this repo's connectors, WebSearch and WebFetch. Excludes any jurisdiction outside the US, and excludes one identified federal statistical report (NIDDK's "Burden of Digestive Diseases in the United States," NBK611384) whose NCBI Bookshelf accession carries no PMID, DOI, ISBN or other identifier in this report's closed vocabulary — see section 5.
Sourcing: A US-specific point prevalence rests on one tertiary JAMA review with no stated primary source of its own; a rigorously pooled but non-US-specific prevalence rests on one large systematic review and meta-analysis; grade-specific US prevalence, incidence, and a stated US trend direction were not found this pass.
Internal hemorrhoids are graded I-IV by degree of prolapse, a convention two independent peer-reviewed sources both use without dispute [1][4]. Point-prevalence estimates for hemorrhoidal disease vary enormously depending on population and diagnostic method: a 2026 systematic review and meta-analysis of 150 studies (8,960,338 individuals) puts the global pooled point prevalence at 25.92% (95% CI 22.62-29.22), with estimates from invasive diagnostic methods running higher than from non-invasive ones [2]. No comparably rigorous, population-representative, US-specific point-prevalence study was located this pass; the one US-specific figure found, "approximately 10 million individuals," comes from a tertiary narrative review that states no primary source of its own [1]. Grade-specific prevalence — the number that would size this candidate's actual grade II-III addressable population — was not found. Pregnancy is the one subgroup with a repeatedly cited elevated-risk figure, though the two sources located state different, non-identical quantities [4][5]. No study reporting a US incidence rate or a stated multi-year US trend direction for hemorrhoidal disease specifically was located this pass.
_Baseline (v1). No prior version; this establishes the starting point for future diffs._
Internal hemorrhoids originate above the dentate line and are classified by degree of prolapse: grade I (confined to the anal canal), grade II (prolapse beyond the anus with spontaneous reduction), grade III (prolapse requiring manual reduction), and grade IV (irreducible) [1]. The AGA's 2026 Clinical Practice Update uses the same four-grade convention independently, referring to "grades 1 to 3" as the office-treatment band and "Grade 4" as requiring surgery [4] — stated plainly, two independent non-affiliated peer-reviewed sources agree on the grading scheme itself.
The only US-specific population prevalence figure located this pass is a single sentence in a 2025 JAMA narrative review: "Hemorrhoidal disease, pathology of the tissue lining of the anal canal, affects approximately 10 million individuals in the US" [1] [single-source]. The review states this in its Importance section with no methods, no stated primary source, and no date range for the underlying estimate — it is a tertiary source's summary claim, not a surveillance study, and it is not grade-stratified. No second, independent source stating a comparable US population-level prevalence figure was located this pass.
A 2026 systematic review and meta-analysis (PROSPERO CRD420251045600) pooled 210 datasets across 150 studies, 8,960,338 individuals total, searched across PubMed, Scopus, Embase, Web of Science and Google Scholar through March 2025: the global pooled point prevalence of haemorrhoidal disease was 25.92% (95% CI 22.62-29.22), lifetime prevalence 27.19% (95% CI 14.77-39.60), and one-year prevalence 21.65% (95% CI 14.33-28.97) [2] [single-source]. The same review reports prevalence "higher in women (27.33%, 95% CI 21.84-32.82) than in men," "highest in the African region (28.07%, 95% CI 15.34-40.79)," and higher when ascertained by "invasive diagnostic methods (28.05%, 95% CI 23.86-32.26)" than non-invasive ones [2] [single-source]. This is a global, cross-national pooled figure, not a US-specific one, and none of its regional subgroups reported in the retrieved abstract corresponds to a US or North American estimate distinct from the pooled global figure. Separately, a 2026 cross-sectional study of 421 self-selected sedentary-occupation professionals (country not stated in the retrieved abstract) found a cohort hemorrhoid prevalence of 38.95%, with higher dietary fiber intake independently associated with lower odds of hemorrhoids (adjusted OR 0.56, 95% CI 0.32-0.98, highest vs. lowest fiber-intake quartile) [7] [single-source]. This figure describes one occupational cohort, not a general population, and the study's own cross-sectional design is stated by its authors as not supporting a causal or general-prevalence inference [7].
No source located this pass reports what share of symptomatic or diagnosed hemorrhoid patients present at grade II-III specifically, as opposed to grade I or grade IV — the single number that would most directly size this domain's addressable population. No source located this pass reports a US or comparable population-level annual incidence rate (new diagnoses per year) for hemorrhoidal disease; every quantity found in this pass is a prevalence or point-in-time proportion, not an incidence rate.
Two sources address pregnancy specifically and state different quantities for different, related conditions. The AGA's 2026 Clinical Practice Update states plainly, as Best Practice Advice 8: "Hemorrhoids occur in up to two-thirds of women during pregnancy" [4] [single-source]. A separate 2026 review of proctological conditions in pregnancy states the broader category of "proctological diseases are highly prevalent during pregnancy, with reported incidence rates ranging from 45% to 68%," adding that "the true prevalence is likely higher due to underreporting" [5] [single-source] — this figure covers proctological conditions generally (hemorrhoids, anal fissure, and perianal thrombosis together), not hemorrhoids alone, so it is directionally consistent with, but not a direct corroboration of, the AGA's two-thirds hemorrhoid-specific figure. Neither source gives a US-specific denominator or sampling frame.
The 2026 meta-analysis reports that, in unadjusted analyses across its pooled studies, "older age, obesity, pregnancy, diabetes, family history, constipation, and hypertension" were associated with hemorrhoidal disease [2] [single-source]. The sedentary-professional cross-sectional study adds a dose-response finding specific to fiber intake, described above [7] [single-source]. No source in this pass reported adjusted, US-population-representative risk-factor estimates.
No source retrieved this pass states a multi-year US trend (rising, falling, or stable) in hemorrhoidal disease prevalence or incidence. A comment-and-response exchange exists in the literature responding to the 2026 meta-analysis [2], visible in PubMed only as bare titles with no abstract text in the record — "Comment on 'Worldwide prevalence of haemorrhoids: a systematic review and meta-analysis'" [3] and the authors' "Response to letter regarding comment on" the same paper [6] — which by their existence indicate the pooled prevalence estimate in [2] drew published methodological pushback, but the substance of that critique was not retrieved this pass; both are paywalled beyond the title [3][6] [paywalled].
[1] Hemorrhoidal Disease: A Review — JAMA (published 2025-08-18; accessed 2026-09-01). PMID 40824576 — https://pubmed.ncbi.nlm.nih.gov/40824576/ [peer-reviewed] [2] Worldwide prevalence of haemorrhoids: a systematic review and meta-analysis — Annals of Medicine (published 2026-12; accessed 2026-09-01). PMID 41450176 — https://pubmed.ncbi.nlm.nih.gov/41450176/ [peer-reviewed] [3] Comment on 'Worldwide prevalence of haemorrhoids: a systematic review and meta-analysis' — Annals of Medicine (published 2026-12; accessed 2026-09-01; abstract not available in the PubMed record, title only). PMID 41741329 — https://pubmed.ncbi.nlm.nih.gov/41741329/ [peer-reviewed] [4] AGA Clinical Practice Update on Diagnosis and Treatment of Hemorrhoids: Expert Review — Clinical Gastroenterology and Hepatology (published 2026-07; accessed 2026-09-01). PMID 42067175 — https://pubmed.ncbi.nlm.nih.gov/42067175/ [peer-reviewed] [5] Incidence, Diagnosis, and Management of Proctological Conditions during Pregnancy — Visceral Medicine (published 2026-02; accessed 2026-09-01). PMID 41064523 — https://pubmed.ncbi.nlm.nih.gov/41064523/ [peer-reviewed] [6] Response to letter regarding comment on "worldwide prevalence of haemorrhoids: a systematic review and meta-analysis" — Annals of Medicine (published 2026-12; accessed 2026-09-01; abstract not available in the PubMed record, title only). PMID 41793125 — https://pubmed.ncbi.nlm.nih.gov/41793125/ [peer-reviewed] [7] Dose-response association between dietary fiber intake and hemorrhoid risk among sedentary professionals: a cross-sectional study — Frontiers in Public Health (published 2026, month not given in the PubMed record; accessed 2026-09-01). PMID 42523786 — https://pubmed.ncbi.nlm.nih.gov/42523786/ [peer-reviewed]
Well established: the four-grade (I-IV) internal hemorrhoid classification rests on two independent, non-affiliated peer-reviewed sources stating the same convention [1][4] and is stated plainly. Nothing else in this report reaches two independent sources agreeing on the same quantity — every prevalence and risk-factor figure below carries its own single-source marker.
Thin: the US-specific "10 million" prevalence figure rests on one tertiary review with no stated primary source [1]. The global 25.92% pooled prevalence, its sex and regional breakdowns, and its risk-factor list all rest on one meta-analysis [2]. The pregnancy prevalence figures rest on one source each, for two related but non-identical conditions [4][5]. The sedentary-cohort 38.95% prevalence rests on one cross-sectional study whose country was not stated in the retrieved abstract [7].
Rescoped from class 3: none. Every proposition in this report is a published measured quantity (prevalence, proportion, odds ratio) reported in a citable primary or secondary document; no question about what a person would do was posed or needed rescoping.
Out of scope: non-US, non-global-aggregate jurisdictions specifically (e.g., single-country prevalence studies outside the pooled meta-analysis) were not individually pursued, per the scope note above.
Not searched vs. not found: Not found — a US population-representative, grade-stratified prevalence study; any study reporting a US or population-level annual incidence rate for hemorrhoidal disease; any study stating a multi-year US trend direction (rising, falling, stable) for hemorrhoidal disease prevalence or incidence; the substantive content of the published comment/response exchange on [2], which exists in PubMed only as titles with no abstract and was not retrieved beyond that [3][6]. Not searched this pass — hemorrhoid-specific extraction from any US national health survey (e.g., NHANES) microdata, as opposed to a review citing one; demographic (race, income, geographic region) breakdowns within the US specifically; a search of the individual studies underlying the 150-study meta-analysis [2] for a US-only subgroup estimate. Separately, and structurally rather than by search effort: NIDDK's "Burden of Digestive Diseases in the United States" (2nd edition, 2025), chapter 9, "Hemorrhoids," was located and read via WebFetch and contains exactly the kind of US-specific ambulatory-visit, emergency-department-visit, hospital-discharge, mortality, and claims-based-prevalence figures this report otherwise lacks, together with a stated 2004-2018 hospital-discharge-rate trend. It is not cited above and none of its figures are reported as findings in section 3, because its NCBI Bookshelf accession (NBK611384) carries no PMID, DOI, ISBN, or other identifier matching this report's closed identifier vocabulary — only a Bookshelf URL, which this repo's sourcing rule treats as "where a thing was," not "the thing." That report should be the first target of any refresh of this file, ideally by locating a PMID-bearing companion journal article restating its hemorrhoid-specific figures, the way NIDDK's aggregate digestive-disease burden report has one (PMID 39588980, which does not itself break out hemorrhoid-specific numbers in its abstract).
[inference] That grade-specific US prevalence has not been separately measured, rather than measured-but-hard-to-find, is this report's own reading of a search that returned no candidate study rather than a large pool of unreviewed candidates — unlike the 44-2,313-record floors returned for broader prevalence queries in this pass, the grade-specific queries run this pass returned 0-4 records total, which is closer to genuine absence than to under-searching.
| Proposition | Evidence class | Resolvable identifier | Dossier section |
|---|---|---|---|
| A 2026 systematic review and meta-analysis of 150 studies (8,960,338 individuals) found a global pooled point prevalence of haemorrhoidal disease of 25.92% (95% CI 22.62-29.22) | 2 published | PMID 41450176 | 1 |
| The same 2026 meta-analysis found prevalence higher in women (27.33%, 95% CI 21.84-32.82) than in men, and highest in the African region (28.07%, 95% CI 15.34-40.79) | 2 published | PMID 41450176 | 1 |
| A 2025 JAMA narrative review states hemorrhoidal disease "affects approximately 10 million individuals in the US" | 2 published | PMID 40824576 | 1 |
| The AGA's 2026 Clinical Practice Update states hemorrhoids "occur in up to two-thirds of women during pregnancy" | 2 published | PMID 42067175 | 1 |
| A 2026 cross-sectional study of 421 sedentary professionals found a cohort hemorrhoid prevalence of 38.95%, with an adjusted OR of 0.56 (95% CI 0.32-0.98) for hemorrhoids in the highest vs. lowest dietary-fiber-intake quartile | 2 published | PMID 42523786 | 1 |