Table 1.

Main characteristics of studies included in the review.

Study	Country	Sample description		Measures of alcohol consumption	Urine screening test to exclude other SUDs	Specific comments
		Type of BD	Phase of BD
van Gorp et al., 1998	USA	25 BD (type not specified) -12 with past AD - 13 without AD 22 HC	All patients euthymic (HRSD<7 and YMRS<6 for 3 consecutive monthly assessments)	None	Yes	Dual patients should be abstinent at least 6 months (mean duration > 8 years) All subjects were male
Levy et al., 2008	USA	63 BD (all type I) - 13 with current AD (past 6 months) - 9 with remitted AD - 41 without history of SUD No HC	All inpatients with acute mood episodes BDI <15, BHS <10 and YMRS <15	Quantity and frequency (e.g., number of standard alcoholic drinks consumed in the past month, days alcohol was used in the past month)	No	Detoxification upon admission was not required for patients with current AD History of SUD other than alcohol was allowed for the dual groups Substance use measures (ASI, AUDIT)
Sanchez-Moreno et al., 2009b	Spain	65 BD (51 type I) - 30 with history of AB/AD - 35 without AB/AD 35 HC	All euthymic outpatients with 6 consecutive months of remission (HRSD ≤ 8 and YMRS ≤ 6)	None	Yes	Dual patients should be abstinent for at least 1 year History of SUD other than alcohol was excluded as per DSM
van der Werf-Eldering et al., 2010	Netherlands	110 BD (91 type I, 19 type II) - 21 with lifetime AUD (13 with current AUD) 75 HC	Outpatients either euthymic (n = 46) or with mild or moderate depressive symptoms (n = 64) Severe depressive symptoms (IDS>38) and manic symptoms (YMRS>7) were exclusion criteria	None	No	Patients with severe AUD (currently needing treatment in specialized setting) were excluded
Shan et al., 2011	Taiwan	69 BD (all type II) - 19 BD with history of AB/AD - 28 BD without AB/AD 22 HC	All patients in remission for at least 2 weeks (HRSD < 7 and YMRS < 6)	For dual patients: g/day	No	History of SUD other than alcohol was excluded as per DSM Duration of abstinence was not reported
Chang et al., 2012	Taiwan	38 BD-I: - 16 with comorbid AD - 22 without history of AD 56 BD-II - 18 with comorbid AD - 38 without history of AD 29 HC	Same as Shan et al., 2011	None	No	Same as Shan et al., 2011 All subjects were male
Levy et al., 2012	USA	55 BD (all type I) - 21 with comorbid AD (previous year) - 34 without SUD No HC	At baseline, all inpatients with acute mood episodes (34 mania, 12 mixed, 9 depression)	Same as Levy et al., 2008	Yes (only at 3-month follow-up)	Detoxification upon admission was not required for patients with AD History of SUD other than alcohol was allowed for the dual group
Marshall et al., 2012	USA	256 BD (201 type I, 36 type II, 19 NOS) - 158 with history of SUD (130 with alcohol) - 98 without SUD 97 HC	Outpatients and inpatients without manic symptoms (YMRS ≤ 7)	None	No	Almost half of the SUD group met criteria for multiple substances Subjects with active or current substance dependence were excluded

AB, alcohol abuse; AD, alcohol dependence; ASI, Addiction Severity Index; AUD, Alcohol Use Disorder; AUDIT, Alcohol Use Disorder Identification Test; BD, bipolar disorder; BDI, Beck Depression Inventory; BHS, Beck Hopelessness Scale; DSM-IV, Diagnostic and Statistical Manual—4th edition; HC, healthy control; HRSD, Hamilton Rating Scale for Depression; IDS, Inventory of Depressive Symptomatology; NOS, not otherwise specified; SUD, substance use disorder; YMRS, Young Mania Rating Scale.