Household economic burden of type-2 diabetes and hypertension comorbidity care in urban-poor Ghana: a mixed methods study by Amon, S, Aikins, M, Haghparast-Bidgoli, H, Kretchy, IA, Arhinful, DK, Baatiema, L, Awuah, RB, Asah-Ayeh, V, Sanuade, OA, Kushitor, SB, Mensah, SK, Kushitor, MK, Grijalva-Eternod, C, Blandford, A, Jennings, H, Koram, K, Antwi, P, Gray, E, Fottrell, E