Falls in people with dementia

..........................................................................7 POPULÄRVETENSKAPLIG SAMMANFATTNING PÅ SVENSKA .............................................................................9 ABBREVIATIONS ...............................................................11 ORIGINAL PAPERS ...........................................................12 INTRODUCTION.................................................................13 Consequences of falls..........................................................................................13 The occurrence of falls........................................................................................14 Risk factors for falls ............................................................................................14 Interventions regarding falls ...............................................................................16 Falls among people with dementia......................................................................17 Risk factors for falls among people with dementia ........................................17 Interventions regarding falls among people with dementia............................21 Dementia .............................................................................................................22 Statistical methods in fall investigations .............................................................24 Rationale for the thesis........................................................................................29 AIMS OF THE THESIS .......................................................30 METHODS ..........................................................................31 Settings and participants .....................................................................................31 Paper 1............................................................................................................32 Paper 2............................................................................................................33 Paper 3............................................................................................................33 Paper 4............................................................................................................33 Ethical approval..............................................................................................34 Study design........................................................................................................34 Data collection ....................................................................................................35 Baseline assessment Paper 1 ..........................................................................36 Baseline assessment Papers 2, 3 and 4 ...........................................................37 The reporting of falls and their circumstances in Papers 1, 2, 3 and 4...........39 Statistical methodology.......................................................................................41 Fall rate...........................................................................................................41 Chi-square test and t-test ................................................................................41 Poisson and negative binomial regression......................................................42 Regression tree ...............................................................................................43 Partial least squares regression.......................................................................44 Transformation of data, imputation, and construction of interaction variables ........................................................................................................................45 RESULTS............................................................................47 The occurrence of falls and injuries ....................................................................47 Fallpredictors in people with and without dementia living in residential care facilities (Paper 1) ...............................................................................................48 Fallpredictors in patients with dementia in a psychogeriatric ward (Paper 2) ....53 Comparison of three statistical methods for analysis of fall predictors (Paper 3) .............................................................................................................................57 Negative binomial regression.........................................................................57 Regression tree ...............................................................................................58 Partial least squares regression.......................................................................61 Circumstances surrounding falls in patients with dementia in a psychogeriatric ward (Paper 4).....................................................................................................62 Time, location, signs, and activity..................................................................62 Gender ............................................................................................................66 High risk circumstances .................................................................................67 DISCUSSION......................................................................69 Walking difficulties.............................................................................................70 Gender.................................................................................................................70 Visual perception ................................................................................................72 Medications.........................................................................................................74 Patterns of fall predictors according to PLS and regression tree analysis...........75 Circumstances surrounding falls in patients with dementia in a psychogeriatric ward.....................................................................................................................78 Methodological considerations ...........................................................................79 Regression tree and PLS ................................................................................80 Time to first fall..............................................................................................83 Ethical considerations .........................................................................................85 Implications for clinical work and future research..............................................86 CONCLUSIONS..................................................................89 ACKNOWLEDGEMENTS ...................................................90 REFERENCES....................................................................92