Companies where the staff have been trimmed and remaining employees work long hours should expect an increase in sickness, stress and conflict, according to a survey.The State of HR Survey, conducted by King’s College London and law firm Speechly Bircham, questioned 550 human resources professionals representing a combined workforce of about two million employees.Nearly 60 per cent of respondents reported an increase in the number of additional hours worked by staff in the past 12 months.Further analysis found significant associations between additional hours worked and increased absence/sickness levels, stress-related problems and the number of grievances lodged. Some 30 percent of those surveyed said grievances had risen in 2010, with relations with senior and line managers the biggest source of grievance, followed by bullying and harassment.Firms that expect increases in working hours over the next 12 months are also expecting rises in grievances, stress and absence, the report says.