Little is known about the burden of rheumatoid arthritis (RA) in South Africa. The aim of this study was to establish the prevalence of RA and coexisting chronic disease list (CDL) conditions in the private health sector of South Africa.
A retrospective, cross-sectional analysis was performed on medicine claims data from 1 January 2014 to 31 December 2014 to establish the prevalence of RA. The cohort of RA patients was then divided into those with and those without CDL conditions, to determine the number and type of CDL conditions per patient, stratified by age group and gender.
A total 4352 (0.5%) patients had RA, of whom 69.3% (3016) presented with CDL conditions. Patients had a median age of 61.31 years (3.38; 98.51), and 74.8% were female. Patients with CDL conditions were older than those patients without (p < 0.001; Cohen’s d = 0.674). Gender had no influence on the presence of CDL conditions (p = 0.456). Men had relatively higher odds for hyperlipidemia (OR 1.83; CI 1.33–2.51; p < 0.001) and lower odds for asthma (OR 0.83; CI 0.48–1.42; p = 0.490) than women. In combination with hyperlipidemia, the odds for asthma were reversed and strongly increased (OR 6.74; CI 2.07–21.93; p = 0.002). The odds for men having concomitant hyperlipidemia, hypertension, type 2 diabetes mellitus and hypothyroidism were insignificant and low (OR 0.40; CI 0.16–1.02; p = 0.055); however, in the absence of hypothyroidism, the odds increased to 3.26 (CI 2.25–4.71; p < 0.001).
Hypothyroidism was an important discriminating factor for comorbidity in men with RA. This study may contribute to the body of evidence about the burden of RA and coexisting chronic conditions in South Africa.
This is a preview of subscription content, log in to check access.
Buy single article
Instant access to the full article PDF.
Tax calculation will be finalised during checkout.
Subscribe to journal
Immediate online access to all issues from 2019. Subscription will auto renew annually.
Tax calculation will be finalised during checkout.
Widmaier EP, Raff H, Strang KT (2011) Vander’s human physiology. The mechanisms of body function. McGraw Hill, New York
Choy E (2012) Understanding the dynamics: pathways involved in the pathogenesis of rheumatoid arthritis. Rheumatology 51(Suppl. 5):v3–v11. https://doi.org/10.1093/rheumatology/kes113
Rindfleisch JA, Muller D (2005) Diagnosis and management of rheumatoid arthritis. Am Fam Phys 72(6):1037–1047
Grøn KL, Ørnbjerg LM, Hetland ML et al (2014) The association of fatigue, comorbidity burden, disease activity, disability and gross domestic product in patients with rheumatoid arthritis. Results from 34 countries participating in the Quest-RA program. Clin Exp Rheumatol 32(6):869–877
Dougados M, Soubrier M, Antunez A et al (2014) Prevalence of comorbidities in rheumatoid arthritis and evaluation of their monitoring: results of an international, cross-sectional study (COMORA). Ann Rheum Dis 73(1):62–68. https://doi.org/10.1136/annrheumdis-2013-204223
National Rheumatoid Arthritis Society of the United Kingdom (2012) The impact of rheumatoid arthritis co-morbidities. http://www.nras.org.uk/data/files/Impact%20of%20RA%20Co-morbidities.pdf. Accessed 26 April 2016
Meghani SH, Buck HG, Dickson VV et al (2013) The conceptualization and measurement of comorbidity: a review of the interprofessional discourse. Nurs Res Pract 2013:192782. https://doi.org/10.1155/2013/192782
Al-Bishri J, Attar SM, Bassuni N, Al-Nofaiey Y, Qutbuddeen H, Al-Harthi S, Subahi S (2013) Comorbidity profile among patients with rheumatoid arthritis and the impact on prescriptions trend. Clin Med Insights Arthritis Musculoskelet Disord 6:11–18. https://doi.org/10.4137/CMAMD.S11481
Michaud K, Wolfe F (2007) Comorbidities in rheumatoid arthritis. Best Pract Res Clin Rheumatol 21(5):885–906. https://doi.org/10.1016/j.berh.2007.06.002
Osiri M, Sattayasomboon Y (2013) Prevalence and out-patient medical costs of comorbid conditions in patients with rheumatoid arthritis. Joint Bone Spine 80(6):608–612. https://doi.org/10.1016/j.jbspin.2013.01.013
Petri H, Maldonato D, Robinson NJ (2010) Data-driven identification of co-morbidities associated with rheumatoid arthritis in a large US health plan claims database. BMC Musculoskelet Disord 11:247. https://doi.org/10.1186/1471-2474-11-247
Council for Medical Schemes (2017) Which chronic diseases are covered? https://www.medicalschemes.com/medical_schemes_pmb/chronic_disease_list.htm. Accessed 15 May 2017
Council for Medical Schemes (2017) The importance of ICD10. https://www.medicalschemes.com/medical_schemes_pmb/ICD-10_codes.htm. Accessed 24 Mar. 2016
Council for Medical Schemes (2017) What are PMBs? https://www.medicalschemes.com/medical_schemes_pmb/index.htm. Accessed 15 May 2017
SAS 9.4® (Statistical Analysis System®). SAS Institute Inc., pp 2002–2012
Petersen J, Maree K (2016) Overview of some of the most popular statistical techniques. In: Maree K (ed) First steps in research, 2nd edn. Van Schaik, Pretoria, pp 249–304
Swanepoel JWH, Swanepoel CJ, Van Graan FC, Allison JS, Santana L (2010) Elementary statistical methods. AndCork, Potchefstroom
Parekh AK, Goodman RA, Gordon C, Koh HK (2011) Managing multiple chronic conditions: a strategic framework for improving health outcomes and quality of life. Public Health Rep 126(4):460–471. https://doi.org/10.1177/003335491112600403
Barnett K, Mercer SW, Norbury M, Watt G, Wyke S, Guthrie B (2012) Epidemiology of multimorbidity and implications for health care, research, and medical education: a cross-sectional study. Lancet 380(9836):37–43. https://doi.org/10.1016/S0140-6736(12)60240-2
Steyn HS (2012) Manual for the determination of effect size indices and practical significance. http://www.nwu.ac.za/content/statcs-effect-size. Accessed 26 April 2016
Luban S, Li ZG (2010) Citrullinated peptide and its relevance to rheumatoid arthritis: an update. Int J Rheum Dis 13(4):284–287. https://doi.org/10.1111/j.1756-185X.2010.01553.x
World Health Organization (2016) Chronic rheumatic conditions. http://www.who.int/chp/topics/rheumatic/en/. Accessed 1 August 2016
Council for Medical Schemes (2009) Invitation to participate in clinical advisory committees on the revision of specific PMBs and to submit it proposals. Summary of Clinical Response from Wyeth South Africa (Pty) Ltd as requested on 20th August 2009. https://www.medicalschemes.com/files/PMB%20Review/WyethSummary_20090828.pdf. Accessed 1 July 2016
Ally MMTM., Visser CC (2010) Rheumatoid arthritis. S Afr Orthop J 9(1):18–23
Alamanos Y, Drosos AA (2005) Epidemiology of adult rheumatoid arthritis. Autoimmun Rev 4(3):130–136. https://doi.org/10.1016/j.autrev.2004.09.002
Wandai M, Aagaard-Hansen J, Day C, Sartorius B, Hofman KJ (2017) Available data sources for monitoring non-communicable diseases and their risk factors in South Africa. S Afr Med J 107(4):331–337. https://doi.org/10.7196/SAMJ.2017.v107i4.11438
Kourilovitch M, Galarza-Maldonado C, Ortiz-Prado E (2014) Diagnosis and classification of rheumatoid arthritis. J Autoimmun 48 49:26–30. https://doi.org/10.1016/j.jaut.2014.01.027
Suta C, Petcu L, Craiu E, Suta M (2015) Sex ratio and age in patients with rheumatoid arthritis. Data from a cohort in South-East Romania. Roman J Rheumatol 24(4):220–225
Baser O, Burkan A, Baser E, Koselerli R, Ertugay E, Altinbas A (2013) Direct medical costs associated with rheumatoid arthritis in Turkey: analysis from national claims database. Rheumatol Int 33(10):2577–2584. https://doi.org/10.1007/s00296-013-2782-4
Cojocaru IM, Silosi I, Vrabie CD, Tanasescu R (2010) Extra-articular manifestations in rheumatoid arthritis. Maedica 5(4):286–291
Gullick NJ, Scott DL (2011) Co-morbidities in established rheumatoid arthritis. Best Pract Res Clin Rheumatol 25(4):469–483. https://doi.org/10.1016/j.berh.2011.10.009
Fortin M, Bravo G, Hudon C, Vanasse A, Lapointe L (2005) Prevalence of multimorbidity among adults seen in family practice. Ann Fam Med 3(3):223–228. https://doi.org/10.1370/afm.272
Cutolo M, Kitas GD, van Riel PLCM. (2014) Burden of disease in treated rheumatoid arthritis patients: going beyond the joint. Semin Arthritis Rheum 43(4):479–488. https://doi.org/10.1016/j.semarthrit.2013.08.004
Van Onna M, Boonen A (2016) The challenging interplay between rheumatoid arthritis, ageing and comorbidities. BMC Musculoskelet Disord 17:184. https://doi.org/10.1186/s12891-016-1038-3
Norton S, Koduri G, Nikiphorou E, Dixey J, Williams P, Young A (2013) A study of baseline prevalence and cumulative incidence of comorbidity and extra-articular manifestations in RA and their impact on outcome. Rheumatology 52(1):99–110. https://doi.org/10.1093/rheumatology/kes262
Shisana O, Labadarios D, Rehle T et al (2014) South African National Health and Nutrition Examination Survey (SANHANES-1). HSRC Press, Cape Town
Burger J, Lubbe M, Serfontein J, Ellis S (2017) A cross-sectional analysis of the association between age and gender and prescribed minimum benefit chronic disease list conditions among South Africans with concomitant hypertension, diabetes and dyslipidaemia. Afr Health Sci 17(1):88–98
Boyer JF, Gourraud PA, Cantagrel A, Davignon JL, Constantin A (2011) Traditional cardiovascular risk factors in rheumatoid arthritis: a meta-analysis. Joint Bone Spine 78(2):179–183. https://doi.org/10.1016/j.jbspin.2010.07.016
Al-Shawwa B, Al-Huniti N, Titus G, Abu-Hasan M (2006) Hypercholesterolemia is a potential risk factor for asthma. J Asthma 43(3):231–233. https://doi.org/10.1080/02770900600567056
The authors would like to thank the Pharmaceutical Benefit Management Company for providing the data to conduct the study.
Disclaimer about previous similar publications
Some of the results of the study were presented as a poster presentation at the European Drug Utilisation Research Group (EuroDURG) Conference 2017, held on the 15th–17th November 2017, at the Technology and Innovation Centre, University of Strathclyde, Glasgow, UK. The poster was entitled “Prevalence of rheumatoid arthritis and associated chronic disease list conditions in the private health sector of South Africa”.
Conflict of interest
Author Olivier has received a master’s bursary from the North-West University (Grant no. 23465174). Authors Burger, Joubert, Lubbe, Naudé and Cockeran declare that they have no conflict of interest.
The study protocol was reviewed and approved by the Health Research Ethics Committee of the Health Research Ethics Commitee of the North-West University (Potcehfstroom campus), Potchefstroom, South Africa, on the July 19, 2016 (Ethics number: NWU-00179-14-A1-02). All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.
Human and animal participants
This study was a retrospective analysis of administrative claims data and does not contain any human participants or animals.
Since the PBMs database contain only retrospective depersonalized claims data, the need for informed consent from each individual patient, medical scheme, prescriber and service provider was waived by the Health Research Ethics Committee.
About this article
Cite this article
Olivier, N., Burger, J., Joubert, R. et al. Chronic disease list conditions in patients with rheumatoid arthritis in the private healthcare sector of South Africa. Rheumatol Int 38, 837–844 (2018). https://doi.org/10.1007/s00296-017-3907-y
- South Africa
- Rheumatoid arthritis
- Medicine claims data
- Chronic disease list