III Workshop Scientifico & XV Congresso della Federazione Nazionale

Sindrome di Prader-Willi Hotel Commodore, Montegrotto Terme (PD), 5-6 settembre 2014

Chirurgia Bariatrica: Pro e Contro

Claudio PaganoDip di Medicina, Università di Padova

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Years of Follow-up

Wei

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Banding

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GBP

Weight loss 10 Years after Bariatric Surgery

Sjostrom et al. NEJM 2004; 351:2683

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Surgical Group (n = 1210) Control Group (n = 1099)

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Symptoms of Sleep Apnea at baseline and 2-year follow-up in surgical and control group.

Karason et al. Arch Int Med 2000;160:1797

Sjostrom et al. NEJM 2007; 357:741

Effects of bariatric surgery on mortality in Swedish Obese Subjects.

Sjostrom et al. Lancet Oncol 2009; 357:741

Effects of bariatric surgery on cancer incidence in obesepatients in Sweden (Swedish Obese Subjects Study):a prospective, controlled intervention trial.

La chirurgia bariatrica per contrastare l’obesità nei pazienti con PWS è un’opzione praticabile

?

E’ efficace ?

E’ sicura ?

Laparoscopic Sleeve Gastrectomy

Bypass Gastrico

BMI 5 anni dopo intervento di BPD

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PRE

PazientiPOST

La letteratura scientifica?

• Frammentaria P

• Potenza statistica insufficiente

• Studi piccoli, case report

• Metodi e tecniche diversi

• Tempi di osservazione diversi

• Modi diversi di esprimere i risultati

Necessità di analisi statistica ad hoc

(Meta-analisi)

Database

PubMed, Google Scholar, Intercollegiate Studies Institute (ISI)

Web of Knowledge.

Retrospective data from the Italian PWS network

Keywords

“prader-willi syndrome” AND “bariatric surgery”

Limits

human subjects, no time limit.

Hand searches of reference lists of relevant literature reviews

were used to complement the computer searches.

Selezione articoli

Statistical analysis

Data were synthesized using meta-analytic methods.

The standardized mean difference was calculated using Hedges' g unbiased

approach. Calculation of effect sizes was based on means, standard deviations,

difference in mean scores and sample sizes of the groups.

Data were statistically pooled by the standard meta-analysis approach, meaning

that studies were weighted by the inverse of the sampling variance.

The random effects model was used as a conservative approach to account for

different sources of variation among studies.

The Q statistic was used to assess heterogeneity among studies.

Categorical characteristics were treated as moderators and intervention

effectiveness was compared across subgroups formed by these moderators.

Continuous characteristics were examined as covariates using random effects

meta-regression. Publication bias was assessed using the Egger's t test

Original queries = 84 articles

Relevant abstracts = 31

Articles read and evaluated= 20

Eligible studied used in the meta-analysis= 9

Excluded = 11

Single patient case Reports used for qualitative

review only = 11

Excluded = 53

PRISMA

Forest Plot

Analisi dei moderatori

Età dei pazientiSessoDurata del follow-upPeso inizialeAnno di pubblicazione

…nessuna relazione

Type of Surgery

Geographyc Distribution

Mortalità

• 7/62 pazienti descritti in letteratura (11%)

• Spesso per cause non connesse a complicanze operatorie o post-operatorie

• Il BMI rimaneva molto elevato anche dopo l’intervento.

Conclusioni (I)

• La chirurgia bariatrica nei pazienti obesi con PWS offre risultati “contrastanti”

• Complessivamente la meta-analisi raggiunge la significatività statistica

• Risultati migliori sembrerebbero essere dati dalla Diversione Bilio-Pancreatica.

Conclusioni (II)

• L’analisi è fortemente limitata dalla qualità degli studi primari

• Counseling nutrizionale ?

• Necessità di standardizzazione e confrontabilità delle procedure

Network, network, network…