Table 5. Effect of smoking at diagnosis on outcome of occupational asthma

First author [ref.]	Main conclusion	SIGN grade	Study type	Exposure/occupation	Subjects n
Merget [10]	+	2-	Cohort study	Platinum salts	275
Descatha [28]	No relationship	2+	Case series	Various HMW and LMW agents	227
Chang-Yeung [32]	+	2-	Longitudinal	Western red cedar	38
Cote [12]	No relationship	2+	Longitudinal	Plicatic acid (Western red cedar)	48
Valentino [29]	No relationship	2+	Longitudinal	TDI	50
Sorgdrager [13]	+	2-	Longitudinal	Fluorides	122
Park [16]	No relationship	2-	Longitudinal	TDI	35
Lozewicz [18]	No relationship	2+	Longitudinal	Isocyanates (TDI, MDI)	56
Anees [31]	No relationship	2+	Longitudinal	Various HMW and LMW agents	156
Malo [20]	No relationship	2+	Longitudinal	Various HMW and LMW agents	80
Mapp [22]	No relationship	2-	Longitudinal	TDI	35
Gassert [39]	No relationship	2-	Longitudinal	Various	55
Labreque [23]	No relationship	2-	Longitudinal	Isocyanates	79
Soyseth [24]	No relationship	2+	Longitudinal	Fluorides	38
Merget [38]	+	2-	Longitudinal	Platinum salts	24

SIGN: Scottish Intercollegiate Guidelines Network; HMW: high molecular weight; LMW: low molecular weight; TDI: toluene diisocyanate; MDI: methylene diphenyl diisocyanate. +: relationship between smoking at diagnosis and worse asthma outcome.