| Literature DB >> 28338838 |
J McLauchlan1, H Innes2,3, J F Dillon4, G Foster5, E Holtham6, S McDonald1, B Wilkes6, S J Hutchinson2,3, W L Irving6.
Abstract
Entities:
Mesh:
Year: 2017 PMID: 28338838 PMCID: PMC5837619 DOI: 10.1093/ije/dyw362
Source DB: PubMed Journal: Int J Epidemiol ISSN: 0300-5771 Impact factor: 9.685
Figure 1Breakdown of HCV Research UK cohort sites (N = 56) and participants (N = 10 184) by geographic region.
Break down of HCV Research UK cohort (N = 10 184) according to recruitment approach and time between first appointment at specialist clinic and enrolment
| Recruitment approach | N (%) | Years from first clinic attendance to enrolment, median (IQR) |
|---|---|---|
| New attender | 1476 (15.2) | 0 (0.0–0.1) |
| Existing attenders | 8039 (82.6) | 3.7 (1.3–8.1) |
| Discharged sustained viral responder | 219 (2.3) | 8.1 (3.2–12.6) |
| Unknown | 450 (–) | 1.7 (1.7–4.3) |
*Percentages exclude individuals with unknown recruitment approach.
Description of the final cohort at the time of enrolment (N = 10 184)
| Characteristic | N (%) | |||
|---|---|---|---|---|
| Demographic factors | Age in years | <16 | 85 (0.8) | |
| 16–44 | 3423 (33.7) | |||
| 45–64 | 5934 (58.4) | |||
| 65+ | 718 (7.1) | |||
| Missing | 24 (0.2) | |||
| mean age (SD) | 48.5 (11.7) | |||
| Gender | Female | 2950 (29.0) | ||
| Male | 7190 (70.6) | |||
| Other/missing | 44 (0.4) | |||
| Ethnic group | White | 8496 (83.4) | ||
| Asian/Asian British | 1004 (9.9) | |||
| Black/African/Caribbean/Black British | 223 (2.2) | |||
| Mixed/multiple ethnic groups | 103 (1.0) | |||
| Other | 256 (2.5) | |||
| Unknown | 102 (1.0) | |||
| Country of birth | UK | 7391 (72.6) | ||
| non-UK | 2591 (25.4) | |||
| NK/missing | 202 (2.0) | |||
| Hepatitis C infection factors | Route of infection/ risk group | Injecting drug use | 5290 (51.9) | |
| Blood transfusion/blood products | 1158 (11.8) | |||
| Born abroad | 1006 (9.9) | |||
| Sexual transmission | 335 (3.3) | |||
| Perinatal transmission | 98 (1.0) | |||
| Other | 1074 (10.6) | |||
| No known risk factor | 657 (6.5) | |||
| Missing | 566 (5.6) | |||
| Estimated duration of infection | <20 yrs | 2840 (27.9) | ||
| 20yrs+ | 4214 (41.4) | |||
| unknown | 3130 (30.7) | |||
| Median duration, years (IQR) | 24 (13–32) | |||
| Genotype | 1 | 4770 (46.8) | ||
| 2 | 446 (4.4) | |||
| 3 | 3646 (35.8) | |||
| 4,5,6 | 338 (3.3) | |||
| Mixed genotype | 14 (0.1) | |||
| Missing/NK | 970 (9.5) | |||
| Clinical factors | Antiviral treatment history | Never treated | 4002 (39.3) | |
| Currently being treated | 1511 (14.8) | |||
| Previously treated and cleared infection (i.e. SVR) | 1366 (13.4) | |||
| Previously failed treatment (i.e. non-SVR) | 2947 (28.9) | |||
| Missing/NK | 358 (3.5) | |||
| Liver-related consequences of hepatitis C infection | Diagnosed with liver cirrhosis | No | 7803 (76.6) | |
| Yes - compensated cirrhosis | 1851 (18.2) | |||
| Yes - decompensated cirrhosis | 530 (5.2) | |||
| Diagnosed with liver cancer | No | 9981 (98.0) | ||
| Yes | 203 (2.0) | |||
| Prior liver transplantation | No | 9674 (95.0) | ||
| Yes | 495 (4.9) | |||
| Unknown | 15 (0.2) | |||
*For individuals who acquired their infection via injecting drug use, the duration of infection was estimated by subtracting the year of enrolment into HCV Research UK from the year of first injection. We then subtracted a further 3 years from this, which relates to the average time from commencing injecting drug use to acquiring HCV infection (Hagan et al, Epidemiology. 2004;15(5):543–9).
Characteristics of patients enrolled into the HCV Research UK cohort compared to all patients attending hepatitis C specialist services in Scotland
| Characteristic | HCV Research UK | Scottish National HCV clinical database | ||
|---|---|---|---|---|
| All centres (N=10,184) | Scottish Centres (N=1785) | All HCV patients attending Scottish specialist services, April 2012–April 2015, (N=9787) | ||
| N(%) | N(%) | N(%) | ||
| Gender | Female | 2950 (29.0) | 496 (27.8) | 2894 (29.6) |
| Male/other/missing | 7234 (71.0) | 1289 (72.2) | 6893 (70.4) | |
| Age in years | <16 | 85 (0.8) | 0 (0.0) | 18 (0.2) |
| 16–44 | 3423 (33.7) | 840 (47.1) | 5671 (57.9) | |
| 45–64 | 5934 (58.4) | 876 (49.1) | 3815 (39.0) | |
| 65+ | 718 (7.1) | 63 (3.5) | 283 (2.9) | |
| Missing | 24 (0.2) | 6 (0.3) | 0 (0.0) | |
| mean age (SD) | 48.5 (11.7) | 45.2 (10.2) | 43.4 (14.3) | |
| Ethnic group | White | 8496 (83.4) | 1697 (95.1) | 9327 (95.3) |
| Asian/Asian British | 1004 (9.9) | 60 (3.4) | 294 (3.0) | |
| Black/African/Caribbean/Black British | 223 (2.2) | 7 (0.4) | 29 (0.3) | |
| Any other | 359 (3.5) | 17 (1.0) | 52 (0.5) | |
| unknown | 102 (1.0) | 4 (0.2) | 85 (0.9) | |
| Route of infection/risk group | Injecting drug use | 5290 (51.9) | 1203 (67.4) | 6031 (61.6) |
| Blood transfusion/blood products | 1158 (11.4) | 168 (9.4) | 530 (5.4) | |
| Sexual transmission | 335 (3.3) | 60 (3.4) | 215 (2.2) | |
| Other | 2178 (21.4) | 168 (9.4) | 548 (5.6) | |
| unknown/ no known risk factor | 1223 (12.0) | 186 (10.4) | 2463 (25.2) | |
*Males collapsed with other/missing category to minimise risk of disclosure and to help maintain confidentiality.
**The “born abroad” risk group for HCV Research UK participants has been collapsed into the “other” category, because no equivalent risk group to “born abroad” exists in the Scottish clinical database. “Perinatal transmission group has also been collapsed into “other” to minimise the risk of disclosure and to help maintain confidentiality.
HCV Research UK cohort: summary of epidemiological and clinical data collected for all participants
| Category | Major variables captured | Time point | |
|---|---|---|---|
| Enrolment | Follow-up (at least bienially following enrolment) | ||
| 1: Socio-demographic factors | gender; age; country of birth; ethnicity; recruitment approach; first clinic attendance date | Y | N/A |
| 2: HCV acquisition | route of infection; estimated year of infection, date of HCV diagnosis | Y | N/A |
| 3: Health risk behaviours | data on: alcohol use; drug use; tobacco smoking; and cannabis smoking | Y | Y |
| 4: Physical characteristics | Height, weight, BMI | Y | Y |
| 5: HCV virology | HCV genotype; HCV genotype subtype; viral RNA positivity status; quantitative viral load | Y | Y |
| 6: Comorbid health conditions | presence of: renal failure; diabetes; cancer; depression; HIV co-infection; coagulation bleeding disorder; cryoglobulinaemia | Y | Y |
| 7: Co-medications taken | use of: anti-diabetics, anti-depressants, anti-retrovirals, hypnotics, immunosupressive drugs; opiate substitution therapy; steroids; statins | Y | Y |
| 8: Liver disease status | data on: liver transplantation; liver biopsies performed; diagnosis of cirrhosis; portal hypertension; diagnosis of decompensated cirrhosis; diagnosis of liver cancer; fibroscan scores. | Y | Y |
| 9: Hepatitis C antiviral treatment | data on HCV antiviral treatment episodes including: outcome (i.e. viral clearance), treatment regimen;duration of treatment and side effects. | Y | Y |
| 10: Routine laboratory data | liver function tests; full blood counts; lipid profile tests; blood sugar tests; and renal function tests | Y | N |
| 11. Vital status | data on date and cause of death | N/A | Y |
Y= Yes; N=No; N/A = not applicable.
Overview of enhanced data collection for strategic subgroups of the HCV Research UK cohort
| Subgroup | N (% of full cohort) | Additional data collected |
|---|---|---|
| Participants taking part in the NHS England early access programme | 806 (7.9%) | Data on : 1) routine laboratory results collected annually; 2) prospective health resource utilisation data |
| Genotype 3 infected participants taking part in STOP-HCV | ∼2000 (19.6%) | Data on : 1)host genotyping for ∼800,000 single nucleotide polymorphisms |
| Participants in the STOP-HCV cirrhosis sub-study | ∼1200 (11.8%) | Data on : 1) routine laboratory results collected annually; 2) viral sequencing on baseline samples; and 3) host genotyping for ∼800,000 single nucleotide polymorphisms |
*Refers to data on all HCV-related clinic visits; treatment of adverse effects from antivirals; and general hospital admissions.
Prevalence of selected health conditions/behaviours among participants of HCV Research UK at the time of enrolment
| Health condition/behaviour | Prevalence among HCV Research UK participants, by gender | Crude prevalence in UK general population | Data source for crude population prevalence |
|---|---|---|---|
| Recent injecting drug use | Male: 7.8% | <1% | UK report to European monitoring centre for drugs and drug addition, 2014 |
| Female: 3.9% | |||
| Past injecting drug use | Male: 62.4% | 1% | |
| Female: 46.6% | |||
| Daily/occasional cannabis use | Male: 27.7% | 7% | |
| Female: 15.8% | |||
| Current tobacco smoker | Male: 58.0% | 19% | Health Survey England, 2014 |
| Female: 45.3% | |||
| Obesity (BMI≥30) | Male: 20.3% | 26% | |
| Female: 24.9% | |||
| Underweight (BMI <18.5) | Male: 2.6% | 2% | |
| Female: 3.5% | |||
| Diagnosed with diabetes | Male: 11.2% | 6% | |
| Female: 9.2% | |||
| Previous suicide attempt | Male: 15.1% | 6% | |
| Female 20.2% | |||
| History of sustained heavy alcohol use† | Male: 43.2% | 2–12%† | |
| Female: 23.6% | |||
| Current excess alcohol use‡ | Male: 8.7% | 18% | |
| Female: 7.7% | |||
| Previous hospital admission for depression | Male: 9.1% | 1% | Innes et al |
| Female: 12.4% | |||
| HIV infected | Male: 6.0% | <1% | Public Health England, 2014 |
| Female: 2.9% |
*Recent defined as within the past six months.
†Past sustained heavy alcohol use defined as drinking >50 units a week for at least 6 months. No directly comparable UK population statistic exists for this. As a lower bound, we have indicated 2% which refers to the prevalence of current alcohol consumption >50 units week taken from Health Survey England. As the upper bound we have indicated 12% which refers to the lower bound estimate added to the proportion of ex-drinkers in the UK population.
‡Current excess alcohol use refers to drinking >21 units in the last 7 days for males, and >14 units/wk for females.