Table 1 Basic characteristic and rheumatic disease outcomes after bariatric surgery in selected studies with their main limitations

Lalmohamed et al. [6]

n = 2079 pts

n = 10,442 controls

60% LAGB, 29% RYGB

2.2 years

Osteoporosis

No increase in OP fracture rate

Retrospective design

Limited follow-up duration

Zhang et al. [7] (meta-analysis)

Five observational trials and one RCT but in pts with T2DM

≠ BS

2.2 to 4.8 years

Osteoporosis

Higher risk for any type of fracture in the surgical group

Fracture risk in non-vertebral sites: 1.42; 1.68 in the upper limbs

Mainly retrospective and observational studies

Comparison between only mixed and restrictive procedures

Rousseau et al. [8]

n = 9300 pts

n = 38,028 sex-matched obese pts

n = 126,760 non-obese controls

41% LAGB, 27% SG, 9% RYGB, 21% BD

4.4 years

Osteoporosis

Postoperative adjusted fracture risk higher in the bariatric group aRR: 1.38

A site-specific effect is suggested

Retrospective nested case control study

Bariatric and obese groups not matched for BMI

Lu et al. [9] (nationwide cohort study)

n = 2064 pts

n = 5027 propensity score-matched subjects

14% malabsorptive procedures, 86% restrictive procedures

4.8 years

Osteoporosis

Increased risk of fracture adjusted HR 1.21; malabsorptive procedures aHR 1.48

Retrospective design

Data on BMI pre-surgery and post-surgery were not available.

Nakamura et al. [10]

n = 258 pts

94% RYGB

7.7 years

Osteoporosis

A twofold increased risk of OP fracture

Retrospective uncontrolled design on review of medical records

Non-standardized data

Groen et al. [13] (systematic review)

13 studies

n = 2286 pts

n = 1551 non-surgical pts

RYGB and LAGB

3 months to 6 years

Knee complaints in knee osteoarthritis

Overall significant improvement in knee pain was seen in 73% out of the used assessments

Mainly uncontrolled prospective studies

No RCTs

Limited follow-up duration

Gill et al. [14] (systematic review)

6 studies

n = 2008 pts

n = 1531 controls

RYGB and LAGB

0.5 to 8 years

Knee and hip osteoarthritis

BS may benefit obese pts with hip or knee OA.

Evidence that standardization of outcome is lacking

Inability to perform a pooled analysis or a meta-analysis due to lack of randomized controlled study

Sparks et al. [20]

n = 53 pts

81% RYGB

12 months and most recent follow-up

Rheumatoid arthritis

Decrease in disease activity and serum inflammatory markers

Less RA-related medication use

At 12 months, 6% of pts had moderate/high disease activity vs 57% at baseline

RUD

SSS

Validated measures not collected consistently

Sethi et al. [27]

n = 21 pts

91% LAGB

6.1 years

Psoriatic arthritis

Decrease in disease severity rating

Retrospective uncontrolled database analysis

SSS

Validated measurement not collected consistently

Abstract

Nielsen et al. [31]

n = 132 pts

≠ BS

6 to 13 months

Gout

Low-quality evidence for gout attacks and achieving serum uric acid targets

A meta-analysis was not possible.

The majorities of included studies were uncontrolled.

The lack of rigorous studies is underlined.

Corcelles et al. [32]

n = 31pts

74% RYGB

3 years

Systemic lupus erythematosus

Decrease in SLE immunosuppression medication requirement

RUD

SSS

Saber et al. [36]

n = 10 pts

RYGB

24.5 months

Fibromyalgia

Decrease in median of pain score and points of tenderness

RUD

SSS

Phone interview

Khoueir et al. [43]

n = 58 pts

62% RYGB

12 months

Low back pain

44% decrease in axial back pain (VAS)

38 pts completed pre and post-op questionnaire

SSS

Limited follow-up duration

Uncontrolled study

Lidar et al. [44]

n = 30 pts

≠ BS

12 months

Low back pain

Axial and radicular back pain decreased after surgery (VAS)

SSS

Uncontrolled study

Vincent et al. [33]

n = 25 pts

72% RYGB

28% LAGB

3 months

Low back pain

54% reduction in mean score change in numeric pain rating scale

SSS

Limited follow-up duration

Melissas et al. [42]

n = 29 pts

VBG

24 years

Low back pain

Improved functional disability scores

SSS

Uncontrolled study