Smoking paradox in the development of psoriatic arthritis among patients with psoriasis: A populationbased study

Uyen-sa Duc tran Nguyen, Yuqing Zhang, Na Lu, Qiong Louie-Gao, Jingbo Niu, Alexis Ogdie, Joel M. Gelfand, Michael P. LaValley, Maureen Dubreuil, Jeffrey A. Sparks, Elizabeth W. Karlson, Hyon K. Choi

Research output: Contribution to journalArticle

Abstract

Objectives Smoking is associated with an increased risk of psoriatic arthritis (PsA) in the general population, but not among patients with psoriasis. We sought to clarify the possible methodological mechanisms behind this paradox. Methods Using 1995-2015 data from The Health Improvement Network, we performed survival analysis to examine the association between smoking and incident PsA in the general population and among patients with psoriasis. We clarified the paradox using mediation analysis and conducted bias sensitivity analyses to evaluate the potential impact of index event bias and quantify its magnitude from uncontrolled/unmeasured confounders. Results O f 6.65 million subjects without PsA at baseline, 225 213 participants had psoriasis and 7057 developed incident PsA. Smoking was associated with an increased risk of PsA in the general population (HR 1.27; 95% CI 1.19 to 1.36), but with a decreased risk among patients with psoriasis (HR 0.91; 95% CI 0.84 to 0.99). Mediation analysis showed that the effect of smoking on the risk of PsA was mediated almost entirely through its effect on psoriasis. Bias-sensitivity analyses indicated that even when the relation of uncontrolled confounders to either smoking or PsA was modest (both HRs=~1.5), it could reverse the biased effect of smoking among patients with psoriasis (HR=0.9). Conclusions In this large cohort representative of the UK general population, smoking was positively associated with PsA risk in the general population, but negatively associated among patients with psoriasis. Conditioning on a causal intermediate variable (psoriasis) may even reverse the association between smoking and PsA, potentially explaining the smoking paradox for the risk of PsA among patients with psoriasis.

Original languageEnglish
Pages (from-to)119-123
Number of pages5
JournalAnnals of the Rheumatic Diseases
Volume77
Issue number1
DOIs
StatePublished - 1 Jan 2018

Fingerprint

Psoriatic Arthritis
Survival Analysis
Psoriasis
Cohort Studies
Smoking
Incidence
Population
United Kingdom

Cite this

Nguyen, Uyen-sa Duc tran ; Zhang, Yuqing ; Lu, Na ; Louie-Gao, Qiong ; Niu, Jingbo ; Ogdie, Alexis ; Gelfand, Joel M. ; LaValley, Michael P. ; Dubreuil, Maureen ; Sparks, Jeffrey A. ; Karlson, Elizabeth W. ; Choi, Hyon K. / Smoking paradox in the development of psoriatic arthritis among patients with psoriasis : A populationbased study. In: Annals of the Rheumatic Diseases. 2018 ; Vol. 77, No. 1. pp. 119-123.
@article{60cfa53dd29c4bc49e8df128c708c410,
title = "Smoking paradox in the development of psoriatic arthritis among patients with psoriasis: A populationbased study",
abstract = "Objectives Smoking is associated with an increased risk of psoriatic arthritis (PsA) in the general population, but not among patients with psoriasis. We sought to clarify the possible methodological mechanisms behind this paradox. Methods Using 1995-2015 data from The Health Improvement Network, we performed survival analysis to examine the association between smoking and incident PsA in the general population and among patients with psoriasis. We clarified the paradox using mediation analysis and conducted bias sensitivity analyses to evaluate the potential impact of index event bias and quantify its magnitude from uncontrolled/unmeasured confounders. Results O f 6.65 million subjects without PsA at baseline, 225 213 participants had psoriasis and 7057 developed incident PsA. Smoking was associated with an increased risk of PsA in the general population (HR 1.27; 95{\%} CI 1.19 to 1.36), but with a decreased risk among patients with psoriasis (HR 0.91; 95{\%} CI 0.84 to 0.99). Mediation analysis showed that the effect of smoking on the risk of PsA was mediated almost entirely through its effect on psoriasis. Bias-sensitivity analyses indicated that even when the relation of uncontrolled confounders to either smoking or PsA was modest (both HRs=~1.5), it could reverse the biased effect of smoking among patients with psoriasis (HR=0.9). Conclusions In this large cohort representative of the UK general population, smoking was positively associated with PsA risk in the general population, but negatively associated among patients with psoriasis. Conditioning on a causal intermediate variable (psoriasis) may even reverse the association between smoking and PsA, potentially explaining the smoking paradox for the risk of PsA among patients with psoriasis.",
author = "Nguyen, {Uyen-sa Duc tran} and Yuqing Zhang and Na Lu and Qiong Louie-Gao and Jingbo Niu and Alexis Ogdie and Gelfand, {Joel M.} and LaValley, {Michael P.} and Maureen Dubreuil and Sparks, {Jeffrey A.} and Karlson, {Elizabeth W.} and Choi, {Hyon K.}",
year = "2018",
month = "1",
day = "1",
doi = "10.1136/annrheumdis-2017-211625",
language = "English",
volume = "77",
pages = "119--123",
journal = "Annals of the Rheumatic Diseases",
issn = "0003-4967",
publisher = "BMJ Publishing Group",
number = "1",

}

Nguyen, UDT, Zhang, Y, Lu, N, Louie-Gao, Q, Niu, J, Ogdie, A, Gelfand, JM, LaValley, MP, Dubreuil, M, Sparks, JA, Karlson, EW & Choi, HK 2018, 'Smoking paradox in the development of psoriatic arthritis among patients with psoriasis: A populationbased study', Annals of the Rheumatic Diseases, vol. 77, no. 1, pp. 119-123. https://doi.org/10.1136/annrheumdis-2017-211625

Smoking paradox in the development of psoriatic arthritis among patients with psoriasis : A populationbased study. / Nguyen, Uyen-sa Duc tran; Zhang, Yuqing; Lu, Na; Louie-Gao, Qiong; Niu, Jingbo; Ogdie, Alexis; Gelfand, Joel M.; LaValley, Michael P.; Dubreuil, Maureen; Sparks, Jeffrey A.; Karlson, Elizabeth W.; Choi, Hyon K.

In: Annals of the Rheumatic Diseases, Vol. 77, No. 1, 01.01.2018, p. 119-123.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Smoking paradox in the development of psoriatic arthritis among patients with psoriasis

T2 - A populationbased study

AU - Nguyen, Uyen-sa Duc tran

AU - Zhang, Yuqing

AU - Lu, Na

AU - Louie-Gao, Qiong

AU - Niu, Jingbo

AU - Ogdie, Alexis

AU - Gelfand, Joel M.

AU - LaValley, Michael P.

AU - Dubreuil, Maureen

AU - Sparks, Jeffrey A.

AU - Karlson, Elizabeth W.

AU - Choi, Hyon K.

PY - 2018/1/1

Y1 - 2018/1/1

N2 - Objectives Smoking is associated with an increased risk of psoriatic arthritis (PsA) in the general population, but not among patients with psoriasis. We sought to clarify the possible methodological mechanisms behind this paradox. Methods Using 1995-2015 data from The Health Improvement Network, we performed survival analysis to examine the association between smoking and incident PsA in the general population and among patients with psoriasis. We clarified the paradox using mediation analysis and conducted bias sensitivity analyses to evaluate the potential impact of index event bias and quantify its magnitude from uncontrolled/unmeasured confounders. Results O f 6.65 million subjects without PsA at baseline, 225 213 participants had psoriasis and 7057 developed incident PsA. Smoking was associated with an increased risk of PsA in the general population (HR 1.27; 95% CI 1.19 to 1.36), but with a decreased risk among patients with psoriasis (HR 0.91; 95% CI 0.84 to 0.99). Mediation analysis showed that the effect of smoking on the risk of PsA was mediated almost entirely through its effect on psoriasis. Bias-sensitivity analyses indicated that even when the relation of uncontrolled confounders to either smoking or PsA was modest (both HRs=~1.5), it could reverse the biased effect of smoking among patients with psoriasis (HR=0.9). Conclusions In this large cohort representative of the UK general population, smoking was positively associated with PsA risk in the general population, but negatively associated among patients with psoriasis. Conditioning on a causal intermediate variable (psoriasis) may even reverse the association between smoking and PsA, potentially explaining the smoking paradox for the risk of PsA among patients with psoriasis.

AB - Objectives Smoking is associated with an increased risk of psoriatic arthritis (PsA) in the general population, but not among patients with psoriasis. We sought to clarify the possible methodological mechanisms behind this paradox. Methods Using 1995-2015 data from The Health Improvement Network, we performed survival analysis to examine the association between smoking and incident PsA in the general population and among patients with psoriasis. We clarified the paradox using mediation analysis and conducted bias sensitivity analyses to evaluate the potential impact of index event bias and quantify its magnitude from uncontrolled/unmeasured confounders. Results O f 6.65 million subjects without PsA at baseline, 225 213 participants had psoriasis and 7057 developed incident PsA. Smoking was associated with an increased risk of PsA in the general population (HR 1.27; 95% CI 1.19 to 1.36), but with a decreased risk among patients with psoriasis (HR 0.91; 95% CI 0.84 to 0.99). Mediation analysis showed that the effect of smoking on the risk of PsA was mediated almost entirely through its effect on psoriasis. Bias-sensitivity analyses indicated that even when the relation of uncontrolled confounders to either smoking or PsA was modest (both HRs=~1.5), it could reverse the biased effect of smoking among patients with psoriasis (HR=0.9). Conclusions In this large cohort representative of the UK general population, smoking was positively associated with PsA risk in the general population, but negatively associated among patients with psoriasis. Conditioning on a causal intermediate variable (psoriasis) may even reverse the association between smoking and PsA, potentially explaining the smoking paradox for the risk of PsA among patients with psoriasis.

UR - http://www.scopus.com/inward/record.url?scp=85038219418&partnerID=8YFLogxK

U2 - 10.1136/annrheumdis-2017-211625

DO - 10.1136/annrheumdis-2017-211625

M3 - Article

C2 - 29102956

AN - SCOPUS:85038219418

VL - 77

SP - 119

EP - 123

JO - Annals of the Rheumatic Diseases

JF - Annals of the Rheumatic Diseases

SN - 0003-4967

IS - 1

ER -